{"id":150,"date":"2019-02-08T21:00:19","date_gmt":"2019-02-08T21:00:19","guid":{"rendered":"https:\/\/courses.lumenlearning.com\/suny-dutchess-precalculus\/chapter\/absolute-value-functions\/"},"modified":"2019-05-14T13:53:15","modified_gmt":"2019-05-14T13:53:15","slug":"absolute-value-functions","status":"web-only","type":"chapter","link":"https:\/\/courses.lumenlearning.com\/suny-dutchess-precalculus\/chapter\/absolute-value-functions\/","title":{"raw":"Absolute Value Functions","rendered":"Absolute Value Functions"},"content":{"raw":"<div class=\"textbox learning-objectives\">\r\n<h3>Learning Objectives<\/h3>\r\nIn this section you will:\r\n<ul>\r\n \t<li>Graph an absolute value function.<\/li>\r\n \t<li>Solve an absolute value equation.<\/li>\r\n \t<li>Solve an absolute value inequality.<\/li>\r\n<\/ul>\r\n<\/div>\r\n<div id=\"Figure_01_06_001\" class=\"medium\">\r\n\r\n[caption id=\"\" align=\"aligncenter\" width=\"488\"]<img src=\"https:\/\/s3-us-west-2.amazonaws.com\/courses-images\/wp-content\/uploads\/sites\/3896\/2019\/02\/08205917\/CNX_Precalc_Figure_01_06_001n.jpg\" alt=\"The Milky Way.\" width=\"488\" height=\"338\" \/> <strong>Figure 1.\u00a0<\/strong>Distances in deep space can be measured in all directions. As such, it is useful to consider distance in terms of absolute values. (credit: \"s58y\"\/Flickr)[\/caption]\r\n\r\n<\/div>\r\n<p id=\"fs-id1165137475222\">Until the 1920s, the so-called spiral nebulae were believed to be clouds of dust and gas in our own galaxy, some tens of thousands of light years away. Then, astronomer Edwin Hubble proved that these objects are galaxies in their own right, at distances of millions of light years. Today, astronomers can detect galaxies that are billions of light years away. Distances in the universe can be measured in all directions. As such, it is useful to consider distance as an absolute value function. In this section, we will investigate <strong><span class=\"no-emphasis\">absolute value functions<\/span><\/strong>.<\/p>\r\n\r\n<div id=\"fs-id1165137426078\" class=\"bc-section section\">\r\n<h3>Understanding Absolute Value<\/h3>\r\n<p id=\"fs-id1165135449691\">Recall that in its basic form[latex]\\text{ }f\\left(x\\right)=|x|,\\text{ }[\/latex]the <strong>absolute value<\/strong> function, is one of our toolkit functions. The <span class=\"no-emphasis\">absolute value<\/span> function is commonly thought of as providing the distance the number is from zero on a number line. Algebraically, for whatever the input value is, the output is the value without regard to sign.<\/p>\r\n\r\n<div id=\"fs-id1165135404116\">\r\n<div class=\"textbox shaded\">\r\n<h3>Absolute Value Function<\/h3>\r\n<p id=\"fs-id1165137832269\">The absolute value function can be defined as a piecewise function<\/p>\r\n\r\n<div id=\"fs-id1165137665354\" class=\"unnumbered\" style=\"text-align: center\">[latex]\\text{ }f\\left(x\\right)=|x|=\\bigg\\{\\begin{array}{ccc}x&amp; \\text{if}&amp; x\\ge 0\\\\ -x&amp; \\text{if}&amp; x&lt;0\\end{array}\\text{ }[\/latex]<\/div>\r\n<\/div>\r\n<\/div>\r\n<div id=\"Example_01_06_01\" class=\"textbox examples\">\r\n<div id=\"fs-id1165137437173\">\r\n<div id=\"fs-id1165137618976\">\r\n<h3>Example 1: Determine a Number within a Prescribed Distance<\/h3>\r\n<p id=\"fs-id1165137761508\">Describe all values[latex]\\text{ }x\\text{ }[\/latex]within or including a distance of 4 from the number 5.<\/p>\r\n\r\n<\/div>\r\n<div id=\"fs-id1165135193649\">[reveal-answer q=\"fs-id1165135193649\"]Show Solution[\/reveal-answer]\r\n[hidden-answer a=\"fs-id1165135193649\"]\r\n<p id=\"fs-id1165135424674\">We want the distance between[latex]\\text{ }x\\text{ }[\/latex]and 5 to be less than or equal to 4. We can draw a number line, such as the one in <a class=\"autogenerated-content\" href=\"#Figure_01_06_002\">(Figure)<\/a>, to represent the condition to be satisfied.<\/p>\r\n\r\n<div id=\"Figure_01_06_002\" class=\"small\">\r\n\r\n[caption id=\"\" align=\"aligncenter\" width=\"487\"]<img src=\"https:\/\/s3-us-west-2.amazonaws.com\/courses-images\/wp-content\/uploads\/sites\/3896\/2019\/02\/08205924\/CNX_Precalc_Figure_01_06_002.jpg\" alt=\"Number line describing the difference of the distance of 4 away from 5.\" width=\"487\" height=\"81\" \/> <strong>Figure 2.<\/strong>[\/caption]\r\n\r\n<\/div>\r\n<p id=\"fs-id1165137772130\">The distance from[latex]\\text{ }x\\text{ }[\/latex]to 5 can be represented using the absolute value as[latex]\\text{ }|x-5|.\\text{ }[\/latex]We want the values of[latex]\\text{ }x\\text{ }[\/latex]that satisfy the condition [latex]|x-5|\\le 4.[\/latex]<\/p>\r\n[\/hidden-answer]\r\n\r\n<\/div>\r\n<div id=\"fs-id1165137656116\">\r\n<h3>Analysis<\/h3>\r\n<p id=\"fs-id1165135161478\">Note that<\/p>\r\n\r\n<div id=\"fs-id1165134394601\" class=\"unnumbered\" style=\"text-align: center\">[latex]\\begin{array}{lll}-4\\le x-5\\hfill &amp; \\begin{array}{ccc}&amp; &amp; \\end{array}\\hfill &amp; x-5\\le 4\\hfill \\\\ \\text{ }\\text{ }\\text{ }\\text{ }1\\le x\\hfill &amp; \\hfill &amp; \\text{ }\\text{ }\\text{ }\\text{ }\\text{ }\\text{ }\\text{ }\\text{ }\\text{ }\\text{ }x\\le 9\\hfill \\end{array}[\/latex]<\/div>\r\n<p id=\"fs-id1165137569650\">So[latex]\\text{ }|x-5|\\le 4\\text{ }[\/latex]is equivalent to[latex]\\text{ }1\\le x\\le 9.[\/latex]<\/p>\r\n<p id=\"fs-id1165137539782\">However, mathematicians generally prefer absolute value notation.<\/p>\r\n\r\n<\/div>\r\n<\/div>\r\n<\/div>\r\n<div id=\"fs-id1165137408957\" class=\"precalculus tryit\">\r\n<h3>Try it #1<\/h3>\r\n<div id=\"ti_01_06_01\">\r\n<div id=\"fs-id1165135394308\">\r\n<p id=\"fs-id1165135394310\">Describe all values[latex]\\text{ }x\\text{ }[\/latex]within a distance of 3 from the number 2.<\/p>\r\n\r\n<\/div>\r\n<div id=\"fs-id1165135160738\">[reveal-answer q=\"fs-id1165135160738\"]Show Solution[\/reveal-answer]\r\n[hidden-answer a=\"fs-id1165135160738\"]\r\n<p id=\"fs-id1165135160739\">[latex]|x-2|\\le 3[\/latex]<\/p>\r\n[\/hidden-answer]\r\n\r\n<\/div>\r\n<\/div>\r\n<\/div>\r\n<div id=\"Example_01_06_02\" class=\"textbox examples\">\r\n<div id=\"fs-id1165137657277\">\r\n<div id=\"fs-id1165137579723\">\r\n<h3>Example 2: Resistance of a Resistor<\/h3>\r\n<p id=\"fs-id1165135203760\">Electrical parts, such as resistors and capacitors, come with specified values of their operating parameters: resistance, capacitance, etc. However, due to imprecision in manufacturing, the actual values of these parameters vary somewhat from piece to piece, even when they are supposed to be the same. The best that manufacturers can do is to try to guarantee that the variations will stay within a specified range, often[latex]\\text{ }\\text{\u00b11%,}\\text{ }\u00b1\\text{5%,}\\text{ }[\/latex]or[latex]\\text{ }\u00b1\\text{10%}\\text{.}[\/latex]<\/p>\r\n<p id=\"fs-id1165135175007\">Suppose we have a resistor rated at 680 ohms,[latex]\\text{ }\u00b15%.\\text{ }[\/latex]Use the absolute value function to express the range of possible values of the actual resistance.<\/p>\r\n\r\n<\/div>\r\n<div id=\"fs-id1165137786481\">[reveal-answer q=\"fs-id1165137786481\"]Show Solution[\/reveal-answer]\r\n[hidden-answer a=\"fs-id1165137786481\"]\r\n<p id=\"fs-id1165137600783\">5% of 680 ohms is 34 ohms. The absolute value of the difference between the actual and nominal resistance should not exceed the stated variability, so, with the resistance[latex]\\text{ }R\\text{ }[\/latex]in ohms,<\/p>\r\n\r\n<div id=\"fs-id1165135176481\" class=\"unnumbered\" style=\"text-align: center\">[latex]|R-680|\\le 34[\/latex][\/hidden-answer]<\/div>\r\n<\/div>\r\n<\/div>\r\n<\/div>\r\n<div id=\"fs-id1165137540249\" class=\"precalculus tryit\">\r\n<h3>Try it #2<\/h3>\r\n<div id=\"ti_01_06_02\">\r\n<div id=\"fs-id1165137828265\">\r\n<p id=\"fs-id1165137828266\">Students who score within 20 points of 80 will pass a test. Write this as a distance from 80 using absolute value notation.<\/p>\r\n\r\n<\/div>\r\n<div id=\"fs-id1165137715310\">[reveal-answer q=\"fs-id1165137715310\"]Show Solution[\/reveal-answer]\r\n[hidden-answer a=\"fs-id1165137715310\"]\r\n<p id=\"fs-id1165134090680\">using the variable[latex]\\text{ }p\\text{ }[\/latex]for passing,[latex]\\text{ }|p-80|\\le 20[\/latex]<\/p>\r\n[\/hidden-answer]\r\n\r\n<\/div>\r\n<\/div>\r\n<\/div>\r\n<\/div>\r\n<div id=\"fs-id1165135186288\" class=\"bc-section section\">\r\n<h3>Graphing an Absolute Value Function<\/h3>\r\n<p id=\"fs-id1165135570012\">The most significant feature of the absolute value graph is the corner point at which the graph changes direction. This point is shown at the <strong><span class=\"no-emphasis\">origin<\/span><\/strong> in <a class=\"autogenerated-content\" href=\"#Figure_01_06_003\">(Figure)<\/a>.<\/p>\r\n\r\n<div id=\"Figure_01_06_003\" class=\"small\">\r\n\r\n[caption id=\"\" align=\"aligncenter\" width=\"487\"]<img src=\"https:\/\/s3-us-west-2.amazonaws.com\/courses-images\/wp-content\/uploads\/sites\/3896\/2019\/02\/08205927\/CNX_Precalc_Figure_01_06_003.jpg\" alt=\"Graph of an absolute function\" width=\"487\" height=\"251\" \/> <strong>Figure 3.<\/strong>[\/caption]\r\n\r\n<\/div>\r\n<p id=\"fs-id1165135639350\"><a class=\"autogenerated-content\" href=\"#Figure_01_06_004\">(Figure)<\/a> shows the graph of[latex]\\text{ }y=2|x\u20133|+4.\\text{ }[\/latex]The graph of[latex]\\text{ }y=|x|\\text{ }[\/latex]has been shifted right 3 units, vertically stretched by a factor of 2, and shifted up 4 units. This means that the corner point is located at[latex]\\text{ }\\left(3,4\\right)\\text{ }[\/latex]for this transformed function.<\/p>\r\n\r\n<div id=\"Figure_01_06_004\" class=\"small\">\r\n\r\n[caption id=\"\" align=\"aligncenter\" width=\"487\"]<img src=\"https:\/\/s3-us-west-2.amazonaws.com\/courses-images\/wp-content\/uploads\/sites\/3896\/2019\/02\/08205930\/CNX_Precalc_Figure_01_06_004.jpg\" alt=\"Graph of the different types of transformations for an absolute function.\" width=\"487\" height=\"486\" \/> <strong>Figure 4.<\/strong>[\/caption]\r\n\r\n<\/div>\r\n<div id=\"Example_01_06_03\" class=\"textbox examples\">\r\n<div id=\"fs-id1165135187768\">\r\n<div id=\"fs-id1165137741094\">\r\n<h3>Example 3: Writing an Equation for an Absolute Value Function<\/h3>\r\n<p id=\"fs-id1165135414332\">Write an equation for the function graphed in <a class=\"autogenerated-content\" href=\"#Figure_01_06_005\">(Figure)<\/a>.<\/p>\r\n\r\n<div id=\"Figure_01_06_005\" class=\"small\">\r\n\r\n[caption id=\"\" align=\"aligncenter\" width=\"487\"]<img src=\"https:\/\/s3-us-west-2.amazonaws.com\/courses-images\/wp-content\/uploads\/sites\/3896\/2019\/02\/08205933\/CNX_Precalc_Figure_01_06_005.jpg\" alt=\"Graph of an absolute function.\" width=\"487\" height=\"363\" \/> <strong>Figure 5.<\/strong>[\/caption]\r\n\r\n<\/div>\r\n<\/div>\r\n<div id=\"fs-id1165137736321\">[reveal-answer q=\"fs-id1165137736321\"]Show Solution[\/reveal-answer]\r\n[hidden-answer a=\"fs-id1165137736321\"]\r\n<p id=\"fs-id1165137680556\">The basic absolute value function changes direction at the origin, so this graph has been shifted to the right 3 units and down 2 units from the basic toolkit function. See <a class=\"autogenerated-content\" href=\"#Figure_01_06_006\">(Figure)<\/a>.<\/p>\r\n\r\n<div id=\"Figure_01_06_006\" class=\"small\">\r\n\r\n[caption id=\"\" align=\"aligncenter\" width=\"487\"]<img src=\"https:\/\/s3-us-west-2.amazonaws.com\/courses-images\/wp-content\/uploads\/sites\/3896\/2019\/02\/08205936\/CNX_Precalc_Figure_01_06_006.jpg\" alt=\"Graph of two transformations for an absolute function at (3, -2).\" width=\"487\" height=\"363\" \/> <strong>Figure 6.<\/strong>[\/caption]\r\n\r\n<\/div>\r\n<p id=\"fs-id1165137805107\">We also notice that the graph appears vertically stretched, because the width of the final graph on a horizontal line is not equal to 2 times the vertical distance from the corner to this line, as it would be for an unstretched absolute value function. Instead, the width is equal to 1 times the vertical distance as shown in <a class=\"autogenerated-content\" href=\"#Figure_01_06_007\">(Figure)<\/a>.<\/p>\r\n\r\n<div id=\"Figure_01_06_007\" class=\"small\">\r\n\r\n[caption id=\"\" align=\"aligncenter\" width=\"487\"]<img src=\"https:\/\/s3-us-west-2.amazonaws.com\/courses-images\/wp-content\/uploads\/sites\/3896\/2019\/02\/08205939\/CNX_Precalc_Figure_01_06_007.jpg\" alt=\"Graph of two transformations for an absolute function at (3, -2) and describes the ratios between the two different transformations.\" width=\"487\" height=\"363\" \/> <strong>Figure 7.<\/strong>[\/caption]\r\n\r\n<\/div>\r\n<p id=\"fs-id1165137732766\">From this information we can write the equation<\/p>\r\n\r\n<div id=\"fs-id1165137425569\" class=\"unnumbered\" style=\"text-align: center\">[latex]\\begin{array}{ll}f\\left(x\\right)=2|x-3|-2,\\hfill &amp; \\text{treating the stretch as a vertical stretch, or}\\hfill \\\\ f\\left(x\\right)=|2\\left(x-3\\right)|-2,\\hfill &amp; \\text{treating the stretch as a horizontal compression}.\\hfill \\end{array}[\/latex][\/hidden-answer]<\/div>\r\n<\/div>\r\n<div id=\"fs-id1165137706602\">\r\n<h3>Analysis<\/h3>\r\n<p id=\"fs-id1165137591631\">Note that these equations are algebraically equivalent\u2014the stretch for an absolute value function can be written interchangeably as a vertical or horizontal stretch or compression.<\/p>\r\n\r\n<\/div>\r\n<\/div>\r\n<\/div>\r\n<div id=\"fs-id1165134377948\" class=\"precalculus qa key-takeaways\">\r\n<h3>Q&amp;A<\/h3>\r\n<p id=\"fs-id1165135245777\"><strong>If we couldn\u2019t observe the stretch of the function from the graphs, could we algebraically determine it?<\/strong><\/p>\r\n<p id=\"fs-id1165137473393\"><em>Yes. If we are unable to determine the stretch based on the width of the graph, we can solve for the stretch factor by putting in a known pair of values for[latex]\\text{ }x\\text{ }[\/latex]and[latex]\\text{ }f\\left(x\\right).[\/latex] <\/em><\/p>\r\n\r\n<div id=\"fs-id1165135514699\" class=\"unnumbered\" style=\"text-align: center\">[latex]f\\left(x\\right)=a|x-3|-2[\/latex]<\/div>\r\n<p id=\"fs-id1165137694034\"><em>Now substituting in the point <\/em>(1, 2)<\/p>\r\n\r\n<div id=\"fs-id1165135173265\" class=\"unnumbered\" style=\"text-align: center\">[latex]\\begin{array}{l}2=a|1-3|-2\\hfill \\\\ 4=2a\\hfill \\\\ a=2\\hfill \\end{array}[\/latex]<\/div>\r\n<\/div>\r\n<div id=\"fs-id1165137611709\" class=\"precalculus tryit\">\r\n<h3>Try it #3<\/h3>\r\n<div id=\"ti_01_06_03\">\r\n<div id=\"fs-id1165134312222\">\r\n<p id=\"fs-id1165135497155\">Write the equation for the absolute value function that is horizontally shifted left 2 units, is vertically flipped, and vertically shifted up 3 units.<\/p>\r\n\r\n<\/div>\r\n<div id=\"fs-id1165137405204\">[reveal-answer q=\"fs-id1165137405204\"]Show Solution[\/reveal-answer]\r\n[hidden-answer a=\"fs-id1165137405204\"]\r\n<p id=\"fs-id1165137758260\">[latex]f\\left(x\\right)=-|x+2|+3[\/latex]<\/p>\r\n[\/hidden-answer]\r\n\r\n<\/div>\r\n<\/div>\r\n<\/div>\r\n<div id=\"fs-id1165135203778\" class=\"precalculus qa key-takeaways\">\r\n<h3>Q&amp;A<\/h3>\r\n<p id=\"fs-id1165137527840\"><strong>Do the graphs of absolute value functions always intersect the vertical axis? The horizontal axis? <\/strong><\/p>\r\n<p id=\"fs-id1165137581861\"><em>Yes, they always intersect the vertical axis. The graph of an absolute value function will intersect the vertical axis when the input is zero. <\/em><\/p>\r\n<p id=\"fs-id1165137444543\"><em>No, they do not always intersect the horizontal axis. The graph may or may not intersect the horizontal axis, depending on how the graph has been shifted and reflected. It is possible for the absolute value function to intersect the horizontal axis at zero, one, or two points (see <a class=\"autogenerated-content\" href=\"#Figure_01_06_008\">(Figure)<\/a>). <\/em><\/p>\r\n\r\n<\/div>\r\n<div id=\"Figure_01_06_008\" class=\"wp-caption aligncenter\">\r\n\r\n[caption id=\"\" align=\"aligncenter\" width=\"975\"]<img src=\"https:\/\/s3-us-west-2.amazonaws.com\/courses-images\/wp-content\/uploads\/sites\/3896\/2019\/02\/08205943\/CNX_Precalc_Figure_01_06_008abc.jpg\" alt=\"Graph of the different types of transformations for an absolute function.\" width=\"975\" height=\"415\" \/> <strong>Figure 8.\u00a0<\/strong>(a) The absolute value function does not intersect the horizontal axis. (b) The absolute value function intersects the horizontal axis at one point. (c) The absolute value function intersects the horizontal axis at two points.[\/caption]\r\n\r\n<\/div>\r\n<div class=\"wp-caption-text\"><\/div>\r\n<\/div>\r\n<div id=\"fs-id1165133257286\" class=\"bc-section section\">\r\n<h3>Solving an Absolute Value Equation<\/h3>\r\n<p id=\"fs-id1165137401775\">Now that we can graph an absolute value function, we will learn how to solve an absolute value equation. To solve an equation such as[latex]\\text{ }8=|2x-6|,\\text{ }[\/latex]we notice that the absolute value will be equal to 8 if the quantity inside the absolute value is 8 or -8. This leads to two different equations we can solve independently.<\/p>\r\n\r\n<div id=\"fs-id1165137583696\" class=\"unnumbered\" style=\"text-align: center\">[latex]\\begin{array}{lll}2x-6=8\\hfill &amp; \\text{or}\\hfill &amp; 2x-6=-8\\hfill \\\\ \\text{ }\\text{ }\\text{ }\\text{ }\\text{ }\\text{ }\\text{ }\\text{ }2x=14\\hfill &amp; \\hfill &amp; \\text{ }\\text{ }\\text{ }\\text{ }\\text{ }\\text{ }\\text{ }\\text{ }\\text{ }2x=-2\\hfill \\\\ \\text{ }\\text{ }\\text{ }\\text{ }\\text{ }\\text{ }\\text{ }\\text{ }\\text{ }\\text{ }\\text{ }x=7\\hfill &amp; \\hfill &amp; \\text{ }\\text{ }\\text{ }\\text{ }\\text{ }\\text{ }\\text{ }\\text{ }\\text{ }\\text{ }\\text{ }\\text{ }x=-1\\hfill \\end{array}[\/latex]<\/div>\r\n<p id=\"fs-id1165137641126\">Knowing how to solve problems involving <strong><span class=\"no-emphasis\">absolute value functions<\/span><\/strong> is useful. For example, we may need to identify numbers or points on a line that are at a specified distance from a given reference point.<\/p>\r\nAn <strong>absolute value equation<\/strong> is an equation in which the unknown variable appears in absolute value bars. For example,\r\n<div id=\"fs-id1165137646929\" class=\"unnumbered\" style=\"text-align: center\">[latex]\\begin{array}{l}|x|=4,\\hfill \\\\ |2x-1|=3\\hfill \\\\ |5x+2|-4=9\\hfill \\end{array}[\/latex]<\/div>\r\n<div id=\"fs-id1165137692078\">\r\n<div class=\"textbox shaded\">\r\n<h3>Solutions to Absolute Value Equations<\/h3>\r\n<p id=\"fs-id1165137809877\">For real numbers[latex]\\text{ }A\\text{ }[\/latex]and[latex]\\text{ }B,\\text{ }[\/latex]an equation of the form[latex]\\text{ }|A|=B,\\text{ }[\/latex]with[latex]\\text{ }B\\ge 0,\\text{ }[\/latex]will have solutions when[latex]\\text{ }A=B\\text{ }[\/latex]or[latex]\\text{ }A=-B.\\text{ }[\/latex]If[latex]\\text{ }B&lt;0,\\text{ }[\/latex]the equation[latex]\\text{ }|A|=B\\text{ }[\/latex]has no solution.<\/p>\r\n\r\n<\/div>\r\n<\/div>\r\n<div id=\"fs-id1165135160087\" class=\"precalculus howto examples\">\r\n<h3>How To<\/h3>\r\n<p id=\"fs-id1165135593248\"><strong>Given the formula for an absolute value function, find the horizontal intercepts of its graph<\/strong>.<\/p>\r\n\r\n<ol id=\"fs-id1165131968095\" type=\"1\">\r\n \t<li>Isolate the absolute value term.<\/li>\r\n \t<li>Use[latex]\\text{ }|A|=B\\text{ }[\/latex]to write[latex]\\text{ }A=B\\text{ }[\/latex]or[latex]\\text{ }\\mathrm{-A}=B,\\text{ }[\/latex]assuming[latex]\\text{ }B&gt;0.[\/latex]<\/li>\r\n \t<li>Solve for[latex]\\text{ }x.\\text{ }[\/latex]<\/li>\r\n<\/ol>\r\n<\/div>\r\n<div id=\"Example_01_06_04\" class=\"textbox examples\">\r\n<div id=\"fs-id1165137619575\">\r\n<div id=\"fs-id1165135309797\">\r\n<h3>Example 4: Finding the Zeros of an Absolute Value Function<\/h3>\r\n<p id=\"fs-id1165137527684\">For the function[latex]\\text{ }f\\left(x\\right)=|4x+1|-7[\/latex], find the values of [latex]x[\/latex] such that [latex]\\text{ }f\\left(x\\right)=0[\/latex].<\/p>\r\n\r\n<\/div>\r\n<div id=\"fs-id1165137405662\">[reveal-answer q=\"fs-id1165137405662\"]Show Solution[\/reveal-answer]\r\n[hidden-answer a=\"fs-id1165137405662\"]\r\n<div id=\"fs-id1165137618972\" class=\"unnumbered\" style=\"text-align: center\">[latex]\\begin{array}{lllllll}0=|4x+1|-7\\hfill &amp; \\hfill &amp; \\hfill &amp; \\hfill &amp; \\hfill &amp; \\hfill &amp; \\text{Substitute 0 for }f\\left(x\\right).\\hfill \\\\ 7=|4x+1|\\hfill &amp; \\hfill &amp; \\hfill &amp; \\hfill &amp; \\hfill &amp; \\hfill &amp; \\text{Isolate the absolute value on one side of the equation}.\\hfill \\\\ \\hfill &amp; \\hfill &amp; \\hfill &amp; \\hfill &amp; \\hfill &amp; \\hfill &amp; \\hfill \\\\ \\hfill &amp; \\hfill &amp; \\hfill &amp; \\hfill &amp; \\hfill &amp; \\hfill &amp; \\hfill \\\\ \\hfill &amp; \\hfill &amp; \\hfill &amp; \\hfill &amp; \\hfill &amp; \\hfill &amp; \\hfill \\\\ 7=4x+1\\hfill &amp; \\text{or}\\hfill &amp; \\hfill &amp; \\hfill &amp; \\hfill &amp; -7=4x+1\\hfill &amp; \\text{Break into two separate equations and solve}.\\hfill \\\\ 6=4x\\hfill &amp; \\hfill &amp; \\hfill &amp; \\hfill &amp; \\hfill &amp; -8=4x\\hfill &amp; \\hfill \\\\ \\hfill &amp; \\hfill &amp; \\hfill &amp; \\hfill &amp; \\hfill &amp; \\hfill &amp; \\hfill \\\\ x=\\frac{6}{4}=1.5\\hfill &amp; \\hfill &amp; \\hfill &amp; \\hfill &amp; \\hfill &amp; \\text{ }x=\\frac{-8}{4}=-2\\hfill &amp; \\hfill \\end{array}[\/latex]<\/div>\r\n<p id=\"fs-id1165137870931\">The function outputs 0 when[latex]\\text{ }x=1.5\\text{ }[\/latex]or[latex]\\text{ }x=-2.[\/latex] See <a class=\"autogenerated-content\" href=\"#Figure_01_06_011\">(Figure)<\/a>.<\/p>\r\n\r\n<div id=\"Figure_01_06_011\" class=\"medium\">\r\n\r\n[caption id=\"\" align=\"aligncenter\" width=\"731\"]<img src=\"https:\/\/s3-us-west-2.amazonaws.com\/courses-images\/wp-content\/uploads\/sites\/3896\/2019\/02\/08205946\/CNX_Precalc_Figure_01_06_011F.jpg\" alt=\"Graph an absolute function with x-intercepts at -2 and 1.5.\" width=\"731\" height=\"476\" \/> <strong>Figure 9.<\/strong>[\/caption]\r\n\r\n[\/hidden-answer]\r\n\r\n<\/div>\r\n<\/div>\r\n<\/div>\r\n<\/div>\r\n<div id=\"fs-id1165137599670\" class=\"precalculus tryit\">\r\n<h3>Try it #4<\/h3>\r\n<div id=\"ti_01_06_04\">\r\n<div id=\"fs-id1165135191411\">\r\n<p id=\"fs-id1165137843093\">For the function[latex]\\text{ }f\\left(x\\right)=|2x-1|-3,[\/latex]find the values of[latex]\\text{ }x\\text{ }[\/latex]such that[latex]\\text{ }f\\left(x\\right)=0.[\/latex]<\/p>\r\n\r\n<\/div>\r\n<div id=\"fs-id1165137939483\">[reveal-answer q=\"fs-id1165137939483\"]Show Solution[\/reveal-answer]\r\n[hidden-answer a=\"fs-id1165137939483\"]\r\n<p id=\"fs-id1165137481390\">[latex]x=-1\\text{ }[\/latex]or[latex]\\text{ }\\text{ }x=2[\/latex]<\/p>\r\n[\/hidden-answer]\r\n\r\n<\/div>\r\n<\/div>\r\n<\/div>\r\n<div id=\"fs-id1165135175321\" class=\"precalculus qa key-takeaways\">\r\n<h3>Q&amp;A<\/h3>\r\n<p id=\"fs-id1165135606935\"><strong>Should we always expect two answers when solving[latex]\\text{ }|A|=B?[\/latex]<\/strong><\/p>\r\n<p id=\"fs-id1165137755892\"><em>No. We may find one, two, or even no answers. For example, there is no solution to<\/em>[latex]\\text{ }2+|3x-5|=1.[\/latex]<\/p>\r\n\r\n<\/div>\r\n<div id=\"fs-id1165137911662\" class=\"precalculus howto examples\">\r\n<h3>How To<\/h3>\r\n<p id=\"fs-id1165137647413\"><strong>Given an absolute value equation, solve it.<\/strong><\/p>\r\n\r\n<ol id=\"fs-id1165137589466\" type=\"1\">\r\n \t<li>Isolate the absolute value term.<\/li>\r\n \t<li>Use[latex]\\text{ }|A|=B\\text{ }[\/latex]to write[latex]\\text{ }A=B\\text{ }[\/latex]or[latex]\\text{ }A=\\mathrm{-B}.[\/latex]<\/li>\r\n \t<li>Solve for[latex]\\text{ }x.[\/latex]<\/li>\r\n<\/ol>\r\n<\/div>\r\n<div id=\"Example_01_06_05\" class=\"textbox examples\">\r\n<div id=\"fs-id1165137727865\">\r\n<div id=\"fs-id1165135195112\">\r\n<h3>example 5: Solving an Absolute Value Equation<\/h3>\r\n<p id=\"fs-id1165137695200\">Solve[latex]\\text{ }1=4|x-2|+2.[\/latex]<\/p>\r\n\r\n<\/div>\r\n<div id=\"fs-id1165137561245\">[reveal-answer q=\"fs-id1165137561245\"]Show Solution[\/reveal-answer]\r\n[hidden-answer a=\"fs-id1165137561245\"]\r\n<p id=\"fs-id1165135210177\">Isolating the absolute value on one side of the equation gives the following.<\/p>\r\n\r\n<div id=\"fs-id1165137732202\" class=\"unnumbered\" style=\"text-align: center\">[latex]\\begin{array}{l}\\text{ }\\text{ }\\text{ }\\text{ }\\text{ }\\text{ }\\text{ }\\text{ }1=4|x-2|+2\\hfill \\\\ \\text{ }\\text{ }-1=4|x-2|\\hfill \\\\ \\text{ }-\\frac{1}{4}=|x-2|\\hfill \\end{array}[\/latex]<\/div>\r\n<p id=\"fs-id1165137611734\">The absolute value always returns a positive value, so it is impossible for the absolute value to equal a negative value. At this point, we notice that this equation has no solutions.<\/p>\r\n[\/hidden-answer]\r\n\r\n<\/div>\r\n<\/div>\r\n<\/div>\r\n<div id=\"fs-id1165137465993\" class=\"precalculus qa key-takeaways\">\r\n<h3>Q&amp;A<\/h3>\r\n<p id=\"fs-id1165137573052\"><strong>In <a class=\"autogenerated-content\" href=\"#Example_01_06_05\">(Example)<\/a>, if[latex]\\text{ }f\\left(x\\right)=1\\text{ }[\/latex]and[latex]\\text{ }g\\left(x\\right)=4|x-2|+2\\text{ }[\/latex]were graphed on the same set of axes, would the graphs intersect?<\/strong><\/p>\r\n<p id=\"fs-id1165137602208\"><em>No. The graphs of[latex]\\text{ }f\\text{ }[\/latex]and[latex]\\text{ }g\\text{ }[\/latex]would not intersect, as shown in <a class=\"autogenerated-content\" href=\"#Figure_01_06_012\">(Figure)<\/a>. This confirms, graphically, that the equation[latex]\\text{ }1=4|x-2|+2\\text{ }[\/latex]has no solution.<\/em><\/p>\r\n\r\n<\/div>\r\n<div id=\"Figure_01_06_012\" class=\"small\">\r\n\r\n[caption id=\"\" align=\"aligncenter\" width=\"487\"]<img src=\"https:\/\/s3-us-west-2.amazonaws.com\/courses-images\/wp-content\/uploads\/sites\/3896\/2019\/02\/08205949\/CNX_Precalc_Figure_01_06_012.jpg\" alt=\"Graph of g(x)=4|x-2|+2 and f(x)=1.\" width=\"487\" height=\"476\" \/> <strong>Figure 10.<\/strong>[\/caption]\r\n\r\n<\/div>\r\n<div class=\"precalculus tryit\">\r\n<h3>Try it #5<\/h3>\r\n<div id=\"ti_01_06_05\">\r\n<div id=\"fs-id1165137735929\">\r\n<p id=\"fs-id1165137735930\">Find where the graph of the function[latex]\\text{ }f\\left(x\\right)=-|x+2|+3\\text{ }[\/latex]intersects the horizontal and vertical axes.<\/p>\r\n\r\n<\/div>\r\n<div id=\"fs-id1165134057566\">[reveal-answer q=\"fs-id1165134057566\"]Show Solution[\/reveal-answer]\r\n[hidden-answer a=\"fs-id1165134057566\"]\r\n<p id=\"fs-id1165137452134\">[latex]f\\left(0\\right)=1,\\text{ }[\/latex]so the graph intersects the vertical axis at[latex]\\text{ }\\left(0,1\\right).\\text{ }[\/latex][latex]\\text{ }f\\left(x\\right)=0\\text{ }[\/latex]when[latex]\\text{ }x=-5\\text{ }[\/latex]and[latex]\\text{ }x=1\\text{ }[\/latex]so the graph intersects the horizontal axis at[latex]\\text{ }\\left(-5,0\\right)\\text{ }[\/latex]and[latex]\\text{ }\\left(1,0\\right).[\/latex]<\/p>\r\n[\/hidden-answer]\r\n\r\n<\/div>\r\n<\/div>\r\n<\/div>\r\n<\/div>\r\n<div id=\"fs-id1165135571678\" class=\"bc-section section\">\r\n<h3>Solving an Absolute Value Inequality<\/h3>\r\n<p id=\"fs-id1165137583863\">Absolute value equations may not always involve equalities. Instead, we may need to solve an equation within a range of values. We would use an absolute value inequality to solve such an equation. An <strong>absolute value inequality<\/strong> is an equation of the form<\/p>\r\n\r\n<div id=\"fs-id1165134065110\" class=\"unnumbered\" style=\"text-align: center\">[latex]|A|&lt;B,|A|\\le B,|A|&gt;B,\\text{ }\\text{ }\\text{or} \\text{ }\\text{ }|A|\\ge B,[\/latex]<\/div>\r\n<p id=\"fs-id1165135154162\">where an expression[latex]\\text{ }A\\text{ }[\/latex](and possibly but not usually[latex]\\text{ }B[\/latex]) depends on a variable[latex]\\text{ }x.\\text{ }[\/latex]Solving the inequality means finding the set of all[latex]\\text{ }x\\text{ }[\/latex]that satisfy the inequality. Usually this set will be an interval or the union of two intervals.<\/p>\r\n<p id=\"fs-id1165137580992\">There are two basic approaches to solving absolute value inequalities: graphical and algebraic. The advantage of the graphical approach is we can read the solution by interpreting the graphs of two functions. The advantage of the algebraic approach is it yields solutions that may be difficult to read from the graph.<\/p>\r\n<p id=\"fs-id1165137557647\">For example, we know that all numbers within 200 units of 0 may be expressed as<\/p>\r\n\r\n<div id=\"fs-id1165137543814\" class=\"unnumbered\" style=\"text-align: center\">[latex]|x|&lt;200\\text{ }\\text{or}\\text{ }-200&lt;x&lt;200\\text{ }[\/latex]<\/div>\r\n<p id=\"fs-id1165137610749\">Suppose we want to know all possible returns on an investment if we could earn some amount of money within $200 of $600. We can solve algebraically for the set of values[latex]\\text{ }x\\text{ }[\/latex] such that the distance between[latex]\\text{ }x\\text{ }[\/latex]and 600 is less than 200. We represent the distance between[latex]\\text{ }x\\text{ }[\/latex] and 600 as[latex]\\text{ }|x-600|.[\/latex]<\/p>\r\n\r\n<div id=\"fs-id1165137755666\" class=\"unnumbered\" style=\"text-align: center\">[latex]\\begin{array}{}\\\\ |x-600|&lt;200\\text{ or }-200&lt;x-600&lt;200\\\\ \\text{ }-200+600&lt;x-600+600&lt;200+600\\\\ \\text{ }400&lt;x&lt;800\\end{array}[\/latex]<\/div>\r\n<p id=\"fs-id1165137804310\">This means our returns would be between $400 and $800.<\/p>\r\n<p id=\"fs-id1165137507358\">Sometimes an absolute value inequality problem will be presented to us in terms of a shifted and\/or stretched or compressed absolute value function, where we must determine for which values of the input the function\u2019s output will be negative or positive.<\/p>\r\n\r\n<div id=\"fs-id1165137667916\" class=\"precalculus howto examples\">\r\n<h3>How To<\/h3>\r\n<p id=\"fs-id1165137502428\"><strong>Given an absolute value inequality of the form[latex]\\text{ }|x-A|\\le B\\text{ }[\/latex]for real numbers[latex]\\text{ }a\\text{ }[\/latex]and[latex]\\text{ }b\\text{ }[\/latex]where[latex]\\text{ }b\\text{ }[\/latex]is positive, solve the absolute value inequality algebraically.<\/strong><\/p>\r\n\r\n<ol id=\"fs-id1165137563287\" type=\"1\">\r\n \t<li>Find boundary points by solving[latex]\\text{ }|x-A|=B.\\text{ }[\/latex]<\/li>\r\n \t<li>Test intervals created by the boundary points to determine where[latex]\\text{ }|x-A|\\le B.[\/latex]<\/li>\r\n \t<li>Write the interval or union of intervals satisfying the inequality in interval, inequality, or set-builder notation.<\/li>\r\n<\/ol>\r\n<\/div>\r\n<div id=\"Example_01_06_06\" class=\"textbox examples\">\r\n<div id=\"fs-id1165135704112\">\r\n<div id=\"fs-id1165137401703\">\r\n<h3>Example 6: Solving an Absolute Value Inequality<\/h3>\r\n<p id=\"fs-id1165135342955\">Solve[latex]\\text{ }|x\\text{ }-5|\\le 4.[\/latex]<\/p>\r\n\r\n<\/div>\r\n<div id=\"fs-id1165137550840\">[reveal-answer q=\"fs-id1165137550840\"]Show Solution[\/reveal-answer]\r\n[hidden-answer a=\"fs-id1165137550840\"]\r\n<p id=\"fs-id1165137645044\">With both approaches, we will need to know first where the corresponding equality is true. In this case we first will find where[latex]\\text{ }|x-5|=4.\\text{ }[\/latex]We do this because the absolute value is a function with no breaks, so the only way the function values can switch from being less than 4 to being greater than 4 is by passing through where the values equal 4. Solve[latex]\\text{ }|x-5|=4.[\/latex]<\/p>\r\n\r\n<div id=\"fs-id1165135341386\" class=\"unnumbered\" style=\"text-align: center\">[latex]\\begin{array}{lll}\\begin{array}{c}x-5=4\\\\ \\text{ }\\text{ }\\text{ }\\text{ }\\text{ }\\text{ }\\text{ }x=9\\end{array}\\hfill &amp; \\text{ }\\text{ }\\text{ }\\text{or}\\text{ }\\text{ }\\text{ }\\hfill &amp; \\begin{array}{c}x-5=-4\\\\ \\text{ }\\text{ }\\text{ }\\text{ }x=1\\end{array}\\hfill \\end{array}\\text{ }[\/latex]<\/div>\r\n<p id=\"fs-id1165137665217\">After determining that the absolute value is equal to 4 at[latex]\\text{ }x=1\\text{ }[\/latex]and[latex]\\text{ }x=9,\\text{ }[\/latex]we know the graph can change only from being less than 4 to greater than 4 at these values. This divides the number line up into three intervals:<\/p>\r\n\r\n<div id=\"fs-id1165137423933\" class=\"unnumbered\" style=\"text-align: center\">[latex]x&lt;1,\\text{ }1&lt;x&lt;9,\\text{ and }x&gt;9.[\/latex]<\/div>\r\n<p id=\"fs-id1165137422669\">To determine when the function is less than 4, we could choose a value in each interval and see if the output is less than or greater than 4, as shown in <a class=\"autogenerated-content\" href=\"#Table_01_06_01\">(Table)<\/a>.<\/p>\r\n\r\n<table style=\"border-collapse: collapse;width: 100%\" border=\"1\">\r\n<tbody>\r\n<tr>\r\n<td style=\"width: 25%;text-align: center\" colspan=\"4\"><strong>Table 1<\/strong><\/td>\r\n<\/tr>\r\n<tr>\r\n<td style=\"width: 25%\"><strong>Interval test<\/strong>[latex]\\text{ }x[\/latex]<\/td>\r\n<td style=\"width: 25%\">[latex]f\\left(x\\right)[\/latex]<\/td>\r\n<td style=\"width: 1.69205%\">[latex]&lt;4\\text{ }[\/latex]or[latex]\\text{ }&gt;4?[\/latex]<\/td>\r\n<td style=\"width: 48.308%\"><\/td>\r\n<\/tr>\r\n<tr>\r\n<td style=\"width: 25%\">[latex]x&lt;1[\/latex]<\/td>\r\n<td style=\"width: 25%\">0<\/td>\r\n<td style=\"width: 1.69205%\">[latex]|0-5|=5[\/latex]<\/td>\r\n<td style=\"width: 48.308%\">Greater than<\/td>\r\n<\/tr>\r\n<tr>\r\n<td style=\"width: 25%\">[latex]1&lt;x&lt;9[\/latex]<\/td>\r\n<td style=\"width: 25%\">6<\/td>\r\n<td style=\"width: 1.69205%\">[latex]|6-5|=1[\/latex]<\/td>\r\n<td style=\"width: 48.308%\">Less than<\/td>\r\n<\/tr>\r\n<tr>\r\n<td style=\"width: 25%\">[latex]x&gt;9[\/latex]<\/td>\r\n<td style=\"width: 25%\">11<\/td>\r\n<td style=\"width: 1.69205%\">[latex]|11-5|=6[\/latex]<\/td>\r\n<td style=\"width: 48.308%\">Greater than<\/td>\r\n<\/tr>\r\n<\/tbody>\r\n<\/table>\r\n<p id=\"fs-id1165137558949\">Because[latex]\\text{ }1\\le x\\le 9\\text{ }[\/latex]is the only interval in which the output at the test value is less than 4, we can conclude that the solution to[latex]\\text{ }|x-5|\\le 4\\text{ }[\/latex]is[latex]\\text{ }1\\le x\\le 9,\\text{ }[\/latex]or[latex]\\text{ }\\left[1,9\\right].[\/latex]<\/p>\r\n<p id=\"fs-id1165137424051\">To use a graph, we can sketch the function[latex]\\text{ }f\\left(x\\right)=|x-5|.\\text{ }[\/latex]To help us see where the outputs are 4, the line[latex]\\text{ }g\\left(x\\right)=4\\text{ }[\/latex]could also be sketched as in <a class=\"autogenerated-content\" href=\"#Figure_01_06_013\">(Figure)<\/a>.<\/p>\r\n\r\n<div id=\"Figure_01_06_013\" class=\"small\">\r\n\r\n[caption id=\"\" align=\"aligncenter\" width=\"487\"]<img src=\"https:\/\/s3-us-west-2.amazonaws.com\/courses-images\/wp-content\/uploads\/sites\/3896\/2019\/02\/08205952\/CNX_Precalc_Figure_01_06_013.jpg\" alt=\"Graph of an absolute function and a vertical line, demonstrating how to see what outputs are less than the vertical line.\" width=\"487\" height=\"288\" \/> <strong>Figure 11.\u00a0<\/strong>Graph to find the points satisfying an absolute value inequality.[\/caption]\r\n\r\n<\/div>\r\n<p id=\"fs-id1165137874583\">We can see the following:<\/p>\r\n\r\n<ul id=\"fs-id1165134148370\">\r\n \t<li>The output values of the absolute value are equal to 4 at[latex]\\text{ }x=1\\text{ }[\/latex]and[latex]\\text{ }x=9.[\/latex]<\/li>\r\n \t<li>The graph of[latex]\\text{ }f\\text{ }[\/latex]is below the graph of[latex]\\text{ }g\\text{ }[\/latex]on[latex]\\text{ }1&lt;x&lt;9.\\text{ }[\/latex]This means the output values of[latex]\\text{ }f\\left(x\\right)\\text{ }[\/latex]are less than the output values of[latex]\\text{ }g\\left(x\\right).[\/latex]<\/li>\r\n \t<li>The absolute value is less than or equal to 4 between these two points, when[latex]\\text{ }1\\le x\\le 9.\\text{ }[\/latex]In interval notation, this would be the interval[latex]\\text{ }\\left[1,9\\right].[\/latex]\r\n<div id=\"Figure_01_06_013\" class=\"small\">[\/hidden-answer]<\/div><\/li>\r\n<\/ul>\r\n<\/div>\r\n<div id=\"fs-id1165135381301\">\r\n<h3>Analysis<\/h3>\r\n<p id=\"fs-id1165135689465\">For absolute value inequalities,<\/p>\r\n\r\n<div id=\"fs-id1165135650752\" class=\"unnumbered\" style=\"text-align: center\">[latex]\\begin{array}{lll}|x-A|&lt;C,\\hfill &amp; \\hfill &amp; |x-A|&gt;C,\\hfill \\\\ \\text{ }\\text{ }\\text{ }\\text{ }-C&lt;x-A&lt;C,\\hfill &amp; \\hfill &amp; x-A&lt;-C\\text{ or }x-A&gt;C.\\hfill \\end{array}[\/latex]<\/div>\r\n<p id=\"fs-id1165135195336\">The[latex]\\text{ }&lt;\\text{ }[\/latex]or[latex]\\text{ }&gt;\\text{ }[\/latex]symbol may be replaced by[latex]\\text{ }\\le \\text{ or }\\ge .[\/latex]<\/p>\r\n<p id=\"fs-id1165135524557\">So, for this example, we could use this alternative approach.<\/p>\r\n\r\n<div id=\"fs-id1165134226778\" class=\"unnumbered\" style=\"text-align: center\">[latex]\\begin{array}{llll}|\\text{ }x-5|\\le 4\\hfill &amp; \\hfill &amp; \\hfill &amp; \\hfill \\\\ \\text{ }\\text{ }\\text{ }\\text{ }\\text{ }\\text{ }\\text{ }-4\\le x-5\\le 4\\hfill &amp; \\hfill &amp; \\hfill &amp; \\text{Rewrite by removing the absolute value bars}.\\hfill \\\\ -4+5\\le x-5+5\\le 4+5\\hfill &amp; \\hfill &amp; \\hfill &amp; \\text{Isolate the }x.\\hfill \\\\ \\text{ }\\text{ }\\text{ }\\text{ }\\text{ }\\text{ }\\text{ }\\text{ }\\text{ }\\text{ }\\text{ }\\text{ }\\text{ }\\text{ }1\\le x\\le 9\\hfill &amp; \\hfill &amp; \\hfill &amp; \\hfill \\end{array}[\/latex]<\/div>\r\n<\/div>\r\n<\/div>\r\n<\/div>\r\n<div id=\"fs-id1165137762260\" class=\"precalculus tryit\">\r\n<h3>Try it #6<\/h3>\r\n<div id=\"ti_01_06_06\">\r\n<div>\r\n<p id=\"fs-id1165137450875\">Solve[latex]\\text{ }|x+2|\\le 6.[\/latex]<\/p>\r\n\r\n<\/div>\r\n<div id=\"fs-id1165137447691\">[reveal-answer q=\"fs-id1165137447691\"]Show Solution[\/reveal-answer]\r\n[hidden-answer a=\"fs-id1165137447691\"]\r\n<p id=\"fs-id1165137447692\">[latex]-8\\le x\\le 4[\/latex]<\/p>\r\n[\/hidden-answer]\r\n\r\n<\/div>\r\n<\/div>\r\n<\/div>\r\n<div id=\"fs-id1165137530158\" class=\"precalculus howto examples\">\r\n<h3>How To<\/h3>\r\n<p id=\"fs-id1165135445865\"><strong>Given an absolute value function, solve for the set of inputs where the output is positive (or negative). <\/strong><\/p>\r\n\r\n<ol id=\"fs-id1165137572514\" type=\"1\">\r\n \t<li>Set the function equal to zero, and solve for the boundary points of the solution set.<\/li>\r\n \t<li>Use test points or a graph to determine where the function\u2019s output is positive or negative.<\/li>\r\n<\/ol>\r\n<\/div>\r\n<div id=\"Example_01_06_07\" class=\"textbox examples\">\r\n<div id=\"fs-id1165137409791\">\r\n<div id=\"fs-id1165137838822\">\r\n<h3>Example 7: Using a Graphical Approach to Solve Absolute Value Inequalities<\/h3>\r\n<p id=\"fs-id1165137933778\">Given the function [latex]f\\left(x\\right)=-\\frac{1}{2}|4x-5|+3,\\text{ }[\/latex] determine the [latex]x\\text{-}[\/latex]values for which the function values are negative.<\/p>\r\n\r\n<\/div>\r\n<div id=\"fs-id1165137921789\">[reveal-answer q=\"fs-id1165137921789\"]Show Solution[\/reveal-answer]\r\n[hidden-answer a=\"fs-id1165137921789\"]\r\n<p id=\"fs-id1165137431799\">We are trying to determine where[latex]\\text{ }f\\left(x\\right)&lt;0,\\text{ }[\/latex]which is when[latex]-\\frac{1}{2}\\text{ }|4x-5|+3&lt;0.[\/latex]We begin by isolating the absolute value.<\/p>\r\n\r\n<div class=\"unnumbered\" style=\"text-align: center\">[latex]\\begin{array}{ll}-\\frac{1}{2}|4x-5|&lt;-3\\begin{array}{cccc}&amp; &amp; &amp; \\end{array}\\hfill &amp; \\text{Multiply both sides by \u20132, and reverse the inequality}.\\hfill \\\\ \\text{ }\\text{ }\\text{ }\\text{ }\\text{ }\\text{ }\\text{ }\\text{ }\\text{ }\\text{ }|4x-5|&gt;6\\hfill &amp; \\hfill \\end{array}[\/latex]<\/div>\r\n<p id=\"fs-id1165135317447\">Next we solve for the equality[latex]\\text{ }|4x-5|=6.[\/latex]<\/p>\r\n\r\n<div id=\"fs-id1165135307916\" class=\"unnumbered\" style=\"text-align: center\">[latex]\\begin{array}{ll}4x-5=6\\text{}\\text{ or}\\hfill \\hfill &amp; 4x-5=-6\\hfill \\\\ 4x-5=6\\hfill &amp; \\text{ }\\text{ }\\text{ }\\text{ }\\text{ }\\text{ }\\text{ }\\text{ }\\text{ }\\text{ }4x=-1\\hfill \\\\ x=\\frac{11}{4}\\hfill &amp; \\text{ }\\text{ }\\text{ }\\text{ }\\text{ }\\text{ }\\text{ }\\text{ }\\text{ }\\text{ }\\text{ }\\text{ }\\text{ }x=-\\frac{1}{4}\\hfill \\end{array}[\/latex]<\/div>\r\n<p id=\"fs-id1165135344887\">Now, we can examine the graph of[latex]\\text{ }f\\text{ }[\/latex]to observe where the output is negative. We will observe where the branches are below the <em>x<\/em>-axis. Notice that it is not even important exactly what the graph looks like, as long as we know that it crosses the horizontal axis at[latex]\\text{ }x=-\\frac{1}{4}\\text{ }[\/latex]and[latex]\\text{ }x=\\frac{11}{4}\\text{ }[\/latex]and that the graph has been reflected vertically. See <a class=\"autogenerated-content\" href=\"#Figure_01_06_014\">(Figure)<\/a><strong>.<\/strong><\/p>\r\n\r\n<div id=\"Figure_01_06_014\" class=\"small\">\r\n\r\n[caption id=\"\" align=\"aligncenter\" width=\"487\"]<img src=\"https:\/\/s3-us-west-2.amazonaws.com\/courses-images\/wp-content\/uploads\/sites\/3896\/2019\/02\/08205955\/CNX_Precalc_Figure_01_06_014.jpg\" alt=\"Graph of an absolute function with x-intercepts at -0.25 and 2.75.\" width=\"487\" height=\"365\" \/> <strong>Figure 12.<\/strong>[\/caption]\r\n\r\n<\/div>\r\n<p id=\"fs-id1165137725461\">We observe that the graph of the function is below the <em>x<\/em>-axis left of[latex]\\text{ }x=-\\frac{1}{4}\\text{ }[\/latex]and right of[latex]\\text{ }x=\\frac{11}{4}.\\text{ }[\/latex]This means the function values are negative to the left of the first horizontal intercept at[latex]\\text{ }x=-\\frac{1}{4},\\text{ }[\/latex]and negative to the right of the second intercept at[latex]\\text{ }x=\\frac{11}{4}.\\text{ }[\/latex]This gives us the solution to the inequality.<\/p>\r\n\r\n<div id=\"fs-id1165137460499\" class=\"unnumbered\" style=\"text-align: center\">[latex]x&lt;-\\frac{1}{4}\\text{\u2003}\\text{or}\\text{\u2003}x&gt;\\frac{11}{4}[\/latex]<\/div>\r\n<p id=\"fs-id1165135502945\">In interval notation, this would be[latex]\\text{ }\\left(-\\infty ,-0.25\\right)\\cup \\left(2.75,\\infty \\right).[\/latex]<\/p>\r\n[\/hidden-answer]\r\n\r\n<\/div>\r\n<\/div>\r\n<\/div>\r\n<div id=\"fs-id1165137805480\" class=\"precalculus tryit\">\r\n<h3>Try it #7<\/h3>\r\n<div id=\"ti_01_06_07\">\r\n<div id=\"fs-id1165137784437\">\r\n<p id=\"fs-id1165137784438\">Solve[latex]\\text{ }-2|k-4|\\le -6.[\/latex]<\/p>\r\n\r\n<\/div>\r\n<div id=\"fs-id1165135547314\">[reveal-answer q=\"fs-id1165135547314\"]Show Solution[\/reveal-answer]\r\n[hidden-answer a=\"fs-id1165135547314\"]\r\n<p id=\"fs-id1165137767092\">[latex]k\\le 1\\text{ }[\/latex]or[latex]\\text{ }k\\ge 7;\\text{ }[\/latex]in interval notation, this would be[latex]\\text{ }\\left(-\\infty ,1\\right]\\cup \\left[7,\\infty \\right)[\/latex]<\/p>\r\n[\/hidden-answer]\r\n\r\n<\/div>\r\n<\/div>\r\n<\/div>\r\n<div id=\"fs-id1165134257615\" class=\"precalculus media\">\r\n<div class=\"textbox shaded\">\r\n<h3>Media:<\/h3>\r\n<p id=\"fs-id1165134332731\">Access these online resources for additional instruction and practice with absolute value.<\/p>\r\n\r\n<ul id=\"fs-id1165137508064\">\r\n \t<li><a href=\"http:\/\/openstax.org\/l\/graphabsvalue\">Graphing Absolute Value Functions<\/a><\/li>\r\n \t<li><a href=\"http:\/\/openstax.org\/l\/graphabsvalue2\">Graphing Absolute Value Functions 2<\/a><\/li>\r\n \t<li><a href=\"http:\/\/openstax.org\/l\/findeqabsval\">Equations of Absolute Value Function<\/a><\/li>\r\n \t<li><a href=\"http:\/\/openstax.org\/l\/findeqabsval2\">Equations of Absolute Value Function 2<\/a><\/li>\r\n \t<li><a href=\"http:\/\/openstax.org\/l\/solveabsvalueeq\">Solving Absolute Value Equations<\/a><\/li>\r\n<\/ul>\r\n<\/div>\r\n<\/div>\r\n<\/div>\r\n<div id=\"fs-id1165133291312\" class=\"textbox key-takeaways\">\r\n<h3>Key Concepts<\/h3>\r\n<ul id=\"fs-id1165135332513\">\r\n \t<li>The absolute value function is commonly used to measure distances between points. See <a class=\"autogenerated-content\" href=\"#Example_01_06_01\">(Figure)<\/a>.<\/li>\r\n \t<li>Applied problems, such as ranges of possible values, can also be solved using the absolute value function. See <a class=\"autogenerated-content\" href=\"#Example_01_06_02\">(Figure)<\/a>.<\/li>\r\n \t<li>The graph of the absolute value function resembles a letter V. It has a corner point at which the graph changes direction. See <a class=\"autogenerated-content\" href=\"#Example_01_06_03\">(Figure)<\/a>.<\/li>\r\n \t<li>In an absolute value equation, an unknown variable is the input of an absolute value function.<\/li>\r\n \t<li>If the absolute value of an expression is set equal to a positive number, expect two solutions for the unknown variable. See <a class=\"autogenerated-content\" href=\"#Example_01_06_04\">(Figure)<\/a>.<\/li>\r\n \t<li>An absolute value equation may have one solution, two solutions, or no solutions. See <a class=\"autogenerated-content\" href=\"#Example_01_06_05\">(Figure)<\/a>.<\/li>\r\n \t<li>An absolute value inequality is similar to an absolute value equation but takes the form [latex]\\text{ }|A|&lt;B,\\text{ }\\text{ }\\text{ }|A|\\le B,\\text{ }\\text{ }\\text{ }\\text{ }|A|&gt;B,\\text{ }\\text{ }\\text{or }\\text{ }\\text{ }|A|\\ge B.[\/latex]It can be solved by determining the boundaries of the solution set and then testing which segments are in the set. See <a class=\"autogenerated-content\" href=\"#Example_01_06_06\">(Figure)<\/a>.<\/li>\r\n \t<li>Absolute value inequalities can also be solved graphically. See <a class=\"autogenerated-content\" href=\"#Example_01_06_07\">(Figure)<\/a>.<\/li>\r\n<\/ul>\r\n<\/div>\r\n<div class=\"textbox exercises\">\r\n<h3>Section Exercise<\/h3>\r\n<div id=\"fs-id1165137406985\" class=\"bc-section section\">\r\n<h4>Verbal<\/h4>\r\n<div id=\"fs-id1165137734873\">\r\n<div id=\"fs-id1165135510060\">\r\n<p id=\"fs-id1165134347447\">1. How do you solve an absolute value equation?<\/p>\r\n\r\n<\/div>\r\n<div id=\"fs-id1165135206149\">[reveal-answer q=\"fs-id1165135206149\"]Show Solution[\/reveal-answer]\r\n[hidden-answer a=\"fs-id1165135206149\"]\r\n<p id=\"fs-id1165135189754\">Isolate the absolute value term so that the equation is of the form[latex]\\text{ }|A|=B.\\text{ }[\/latex]Form one equation by setting the expression inside the absolute value symbol,[latex]\\text{ }A,\\text{ }[\/latex]equal to the expression on the other side of the equation,[latex]\\text{ }B.\\text{ }[\/latex]Form a second equation by setting[latex]\\text{ }A\\text{ }[\/latex]equal to the opposite of the expression on the other side of the equation,[latex]\\text{ }-B.\\text{ }[\/latex]Solve each equation for the variable.<\/p>\r\n[\/hidden-answer]\r\n\r\n<\/div>\r\n<\/div>\r\n<div id=\"fs-id1165137593210\">\r\n<div id=\"fs-id1165131968049\">\r\n<p id=\"fs-id1165135440055\">2. How can you tell whether an absolute value function has two <em>x<\/em>-intercepts without graphing the function?<\/p>\r\n\r\n<\/div>\r\n<\/div>\r\n<div id=\"fs-id1165133103957\">\r\n<div id=\"fs-id1165133103959\">\r\n\r\n3. When solving an absolute value function, the isolated absolute value term is equal to a negative number. What does that tell you about the graph of the absolute value function?\r\n\r\n<\/div>\r\n<div id=\"fs-id1165134475281\">[reveal-answer q=\"fs-id1165134475281\"]Show Solution[\/reveal-answer]\r\n[hidden-answer a=\"fs-id1165134475281\"]\r\n<p id=\"fs-id1165137662762\">The graph of the absolute value function does not cross the[latex]\\text{ }x[\/latex]-axis, so the graph is either completely above or completely below the[latex]\\text{ }x[\/latex]-axis.<\/p>\r\n[\/hidden-answer]\r\n\r\n<\/div>\r\n<\/div>\r\n<div id=\"fs-id1165135264708\">\r\n<div id=\"fs-id1165135149122\">\r\n<p id=\"fs-id1165135149124\">4. How can you use the graph of an absolute value function to determine the <em>x<\/em>-values for which the function values are negative?<\/p>\r\n\r\n<\/div>\r\n<\/div>\r\n<div id=\"fs-id1165137645236\">\r\n<div id=\"fs-id1165135414273\">\r\n<p id=\"fs-id1165137475324\">5. How do you solve an absolute value inequality algebraically?<\/p>\r\n\r\n<\/div>\r\n<div id=\"fs-id1165135533156\">[reveal-answer q=\"fs-id1165135533156\"]Show Solution[\/reveal-answer]\r\n[hidden-answer a=\"fs-id1165135533156\"]\r\n<p id=\"fs-id1165135533157\">First determine the boundary points by finding the solution(s) of the equation. Use the boundary points to form possible solution intervals. Choose a test value in each interval to determine which values satisfy the inequality.<\/p>\r\n[\/hidden-answer]\r\n\r\n<\/div>\r\n<\/div>\r\n<\/div>\r\n<div id=\"fs-id1165134273549\" class=\"bc-section section\">\r\n<h4>Algebraic<\/h4>\r\n<div id=\"fs-id1165137841613\">\r\n<div id=\"fs-id1165137841615\">\r\n<p id=\"fs-id1165137579699\">6. Describe all numbers[latex]\\text{ }x\\text{ }[\/latex]that are at a distance of 4 from the number 8. Express this using absolute value notation.<\/p>\r\n\r\n<\/div>\r\n<\/div>\r\n<div id=\"fs-id1165135445894\">\r\n<div>\r\n<p id=\"fs-id1165135169187\">7. Describe all numbers[latex]\\text{ }x\\text{ }[\/latex]that are at a distance of[latex]\\text{ }\\frac{1}{2}\\text{ }[\/latex]from the number \u22124. Express this using absolute value notation.<\/p>\r\n\r\n<\/div>\r\n<div id=\"fs-id1165135356596\">[reveal-answer q=\"fs-id1165135356596\"]Show Solution[\/reveal-answer]\r\n[hidden-answer a=\"fs-id1165135356596\"]\r\n<p id=\"fs-id1165134278683\">[latex]\\text{ }|x+4|=\\frac{1}{2}\\text{ }[\/latex]<\/p>\r\n[\/hidden-answer]\r\n\r\n<\/div>\r\n<\/div>\r\n<div id=\"fs-id1165137542576\">\r\n<div id=\"fs-id1165137648320\">\r\n<p id=\"fs-id1165137648322\">8. Describe the situation in which the distance that point[latex]\\text{ }x\\text{ }[\/latex]is from 10 is at least 15 units. Express this using absolute value notation.<\/p>\r\n\r\n<\/div>\r\n<\/div>\r\n<div id=\"fs-id1165134057540\">\r\n<div id=\"fs-id1165137464076\">\r\n<p id=\"fs-id1165137464078\">9. Find all function values[latex]\\text{ }f\\left(x\\right)\\text{ }[\/latex]such that the distance from[latex]\\text{ }f\\left(x\\right)\\text{ }[\/latex]to the value 8 is less than 0.03 units. Express this using absolute value notation.<\/p>\r\n\r\n<\/div>\r\n<div id=\"fs-id1165137541376\">[reveal-answer q=\"fs-id1165137541376\"]Show Solution[\/reveal-answer]\r\n[hidden-answer a=\"fs-id1165137541376\"]\r\n<p id=\"fs-id1165137572565\">[latex]|f\\left(x\\right)-8|&lt;0.03[\/latex]<\/p>\r\n[\/hidden-answer]\r\n\r\n<\/div>\r\n<\/div>\r\n<p id=\"fs-id1165137658780\">For the following exercises, solve the equations below and express the answer using set notation.<\/p>\r\n\r\n<div id=\"fs-id1165137547457\">\r\n<div id=\"fs-id1165135176655\">\r\n<p id=\"fs-id1165137823605\">10. [latex]|x+3|=9[\/latex]<\/p>\r\n\r\n<\/div>\r\n<\/div>\r\n<div id=\"fs-id1165135254647\">\r\n<div id=\"fs-id1165135254649\">\r\n<p id=\"fs-id1165135253828\">11. [latex]|6-x|=5[\/latex]<\/p>\r\n\r\n<\/div>\r\n<div id=\"fs-id1165137424495\">[reveal-answer q=\"fs-id1165137424495\"]Show Solution[\/reveal-answer]\r\n[hidden-answer a=\"fs-id1165137424495\"]\r\n<p id=\"fs-id1165137424497\">[latex]\\left\\{1,11\\right\\}[\/latex]<\/p>\r\n[\/hidden-answer]\r\n\r\n<\/div>\r\n<\/div>\r\n<div id=\"fs-id1165137930354\">\r\n<div id=\"fs-id1165137930356\">\r\n<p id=\"fs-id1165137639146\">12. [latex]|5x-2|=11[\/latex]<\/p>\r\n\r\n<\/div>\r\n<\/div>\r\n<div id=\"fs-id1165137594492\">\r\n<div id=\"fs-id1165137594494\">\r\n<p id=\"fs-id1165137436276\">13. [latex]|4x-2|=11[\/latex]<\/p>\r\n\r\n<\/div>\r\n<div id=\"fs-id1165137600494\">[reveal-answer q=\"fs-id1165137600494\"]Show Solution[\/reveal-answer]\r\n[hidden-answer a=\"fs-id1165137600494\"][latex]\\left\\{\\frac{9}{4},\\text{ }\\text{ }\\text{ }\\text{ }\\text{ }\\frac{13}{4}\\right\\}[\/latex][\/hidden-answer]<\/div>\r\n<\/div>\r\n<div id=\"fs-id1165135440214\">\r\n<div id=\"fs-id1165137833911\">\r\n<p id=\"fs-id1165137833914\">14. [latex]2|4-x|=7[\/latex]<\/p>\r\n\r\n<\/div>\r\n<\/div>\r\n<div id=\"fs-id1165135641672\">\r\n<div id=\"fs-id1165135641675\">\r\n<p id=\"fs-id1165137410330\">15. [latex]3|5-x|=5[\/latex]<\/p>\r\n\r\n<\/div>\r\n<div id=\"fs-id1165137411215\">[reveal-answer q=\"fs-id1165137411215\"]Show Solution[\/reveal-answer]\r\n[hidden-answer a=\"fs-id1165137411215\"]\r\n<p id=\"fs-id1165137411217\">[latex]\\left\\{\\frac{10}{3},\\text{ }\\text{ }\\text{ }\\text{ }\\text{ }\\frac{20}{3}\\right\\}[\/latex]<\/p>\r\n[\/hidden-answer]\r\n\r\n<\/div>\r\n<\/div>\r\n<div id=\"fs-id1165135241396\">\r\n<div id=\"fs-id1165135192397\">\r\n<p id=\"fs-id1165135192399\">16. [latex]3|x+1|-4=5[\/latex]<\/p>\r\n\r\n<\/div>\r\n<\/div>\r\n<div id=\"fs-id1165137451880\">\r\n<div id=\"fs-id1165137451883\">\r\n<p id=\"fs-id1165137439227\">17. [latex]5|x-4|-7=2[\/latex]<\/p>\r\n\r\n<\/div>\r\n<div>\r\n<p id=\"fs-id1165134108517\">[reveal-answer q=\"612972\"]Show Solution[\/reveal-answer]\r\n[hidden-answer a=\"612972\"]<\/p>\r\n[latex]\\left\\{\\frac{11}{5},\\text{ }\\text{ }\\text{ }\\text{ }\\text{ }\\frac{29}{5}\\right\\}[\/latex][\/hidden-answer]\r\n\r\n<\/div>\r\n<\/div>\r\n<div id=\"fs-id1165137803650\">\r\n<div id=\"fs-id1165137803652\">\r\n<p id=\"fs-id1165135613399\">18. [latex]0=-|x-3|+2[\/latex]<\/p>\r\n\r\n<\/div>\r\n<\/div>\r\n<div id=\"fs-id1165137442574\">\r\n<div id=\"fs-id1165137442576\">\r\n\r\n19. [latex]2|x-3|+1=2[\/latex]\r\n\r\n<\/div>\r\n<div id=\"fs-id1165135151997\">[reveal-answer q=\"fs-id1165135151997\"]Show Solution[\/reveal-answer]\r\n[hidden-answer a=\"fs-id1165135151997\"]\r\n<p id=\"fs-id1165137585705\">[latex]\\left\\{\\frac{5}{2},\\frac{7}{2}\\right\\}[\/latex]<\/p>\r\n[\/hidden-answer]\r\n\r\n<\/div>\r\n<\/div>\r\n<div id=\"fs-id1165137761108\">\r\n<div id=\"fs-id1165131911969\">\r\n<p id=\"fs-id1165131911971\">20. [latex]|3x-2|=7[\/latex]<\/p>\r\n\r\n<\/div>\r\n<\/div>\r\n<div id=\"fs-id1165137838065\">\r\n<div id=\"fs-id1165137571104\">\r\n<p id=\"fs-id1165137571106\">21. [latex]|3x-2|=-7[\/latex]<\/p>\r\n\r\n<\/div>\r\n<div id=\"fs-id1165137809984\">[reveal-answer q=\"fs-id1165137809984\"]Show Solution[\/reveal-answer]\r\n[hidden-answer a=\"fs-id1165137809984\"]\r\n<p id=\"fs-id1165135182933\">No solution<\/p>\r\n[\/hidden-answer]\r\n\r\n<\/div>\r\n<\/div>\r\n<div id=\"fs-id1165137793832\">\r\n<div id=\"fs-id1165134393100\">\r\n<p id=\"fs-id1165134393102\">22. [latex]|\\frac{1}{2}x-5|=11[\/latex]<\/p>\r\n\r\n<\/div>\r\n<\/div>\r\n<div id=\"fs-id1165137401505\">\r\n<div id=\"fs-id1165137401507\">\r\n<p id=\"fs-id1165137852038\">23. [latex]|\\frac{1}{3}x+5|=14[\/latex]<\/p>\r\n\r\n<\/div>\r\n<div id=\"fs-id1165137854997\">[reveal-answer q=\"fs-id1165137854997\"]Show Solution[\/reveal-answer]\r\n[hidden-answer a=\"fs-id1165137854997\"]\r\n<p id=\"fs-id1165137564109\">[latex]\\left\\{-57,27\\right\\}[\/latex]<\/p>\r\n[\/hidden-answer]\r\n\r\n<\/div>\r\n<\/div>\r\n<div id=\"fs-id1165135160638\">\r\n<div id=\"fs-id1165137769919\">\r\n<p id=\"fs-id1165137769921\">24. [latex]-|\\frac{1}{3}x+5|+14=0[\/latex]<\/p>\r\n\r\n<\/div>\r\n<\/div>\r\n<p id=\"fs-id1165137589731\">For the following exercises, find the <em>x<\/em>- and <em>y<\/em>-intercepts of the graphs of each function.<\/p>\r\n\r\n<div id=\"fs-id1165135190614\">\r\n<div id=\"fs-id1165134117307\">\r\n<p id=\"fs-id1165134117309\">25. [latex]f\\left(x\\right)=2|x+1|-10[\/latex]<\/p>\r\n\r\n<\/div>\r\n<div id=\"fs-id1165134557389\">[reveal-answer q=\"fs-id1165134557389\"]Show Solution[\/reveal-answer]\r\n[hidden-answer a=\"fs-id1165134557389\"]\r\n<p id=\"fs-id1165134557391\">[latex]\\left(0,-8\\right);\\text{ }\\left(-6,0\\right),\\text{ }\\left(4,0\\right)[\/latex]<\/p>\r\n[\/hidden-answer]\r\n\r\n<\/div>\r\n<\/div>\r\n<div id=\"fs-id1165134401702\">\r\n<div id=\"fs-id1165135362510\">\r\n<p id=\"fs-id1165135362512\">26. [latex]f\\left(x\\right)=4|x-3|+4[\/latex]<\/p>\r\n\r\n<\/div>\r\n<\/div>\r\n<div id=\"fs-id1165137824535\">\r\n<div id=\"fs-id1165137824537\">\r\n<p id=\"fs-id1165134220856\">27. [latex]f\\left(x\\right)=-3|x-2|-1[\/latex]<\/p>\r\n\r\n<\/div>\r\n<div>\r\n<p id=\"fs-id1165137433352\">[reveal-answer q=\"453586\"]Show Solution[\/reveal-answer]\r\n[hidden-answer a=\"453586\"]<\/p>\r\n[latex]\\left(0,-7\\right);\\text{ }[\/latex]no[latex]\\text{ }x[\/latex]-intercepts[\/hidden-answer]\r\n\r\n<\/div>\r\n<\/div>\r\n<div id=\"fs-id1165134371172\">\r\n<div id=\"fs-id1165134371174\">\r\n<p id=\"fs-id1165137590699\">28. [latex]f\\left(x\\right)=-2|x+1|+6[\/latex]<\/p>\r\n\r\n<\/div>\r\n<\/div>\r\n<p id=\"fs-id1165134117280\">For the following exercises, solve each inequality and write the solution in interval notation.<\/p>\r\n\r\n<div id=\"fs-id1165137656160\">\r\n<div id=\"fs-id1165137656163\">\r\n<p id=\"fs-id1165137938872\">29. [latex]|x-2|&gt;10[\/latex]<\/p>\r\n\r\n<\/div>\r\n<div id=\"fs-id1165137427184\">[reveal-answer q=\"fs-id1165137427184\"]Show Solution[\/reveal-answer]\r\n[hidden-answer a=\"fs-id1165137427184\"]\r\n<p id=\"fs-id1165137427186\">[latex]\\left(-\\infty ,-8\\right)\\cup \\left(12,\\infty \\right)[\/latex]<\/p>\r\n[\/hidden-answer]\r\n\r\n<\/div>\r\n<\/div>\r\n<div id=\"fs-id1165137407052\">\r\n<div id=\"fs-id1165135508305\">\r\n<p id=\"fs-id1165135508307\">30. [latex]2|v-7|-4\\ge 42[\/latex]<\/p>\r\n\r\n<\/div>\r\n<\/div>\r\n<div id=\"fs-id1165135187122\">\r\n<div id=\"fs-id1165135187125\">\r\n<p id=\"fs-id1165137418895\">31. [latex]|3x-4|\\le 8[\/latex]<\/p>\r\n\r\n<\/div>\r\n<div id=\"fs-id1165137445354\">[reveal-answer q=\"fs-id1165137445354\"]Show Solution[\/reveal-answer]\r\n[hidden-answer a=\"fs-id1165137445354\"]\r\n<p id=\"fs-id1165137715044\">[latex]\\frac{-4}{3}\\le x\\le 4[\/latex]<\/p>\r\n[\/hidden-answer]\r\n\r\n<\/div>\r\n<\/div>\r\n<div id=\"fs-id1165135320061\">\r\n<div>\r\n<p id=\"fs-id1165135195164\">32. [latex]|x-4|\\ge 8[\/latex]<\/p>\r\n\r\n<\/div>\r\n<\/div>\r\n<div id=\"fs-id1165135196794\">\r\n<div id=\"fs-id1165135196796\">\r\n<p id=\"fs-id1165135641739\">33. [latex]|3x-5|\\ge 13[\/latex]<\/p>\r\n\r\n<\/div>\r\n<div id=\"fs-id1165137812206\">[reveal-answer q=\"fs-id1165137812206\"]Show Solution[\/reveal-answer]\r\n[hidden-answer a=\"fs-id1165137812206\"][latex]\\left(-\\infty ,-\\frac{8}{3}\\right]\\cup \\left[6,\\infty \\right)[\/latex][\/hidden-answer]<\/div>\r\n<\/div>\r\n<div>\r\n<div id=\"fs-id1165137448163\">\r\n<p id=\"fs-id1165137448165\">34. [latex]|3x-5|\\ge -13[\/latex]<\/p>\r\n\r\n<\/div>\r\n<\/div>\r\n<div id=\"fs-id1165135149793\">\r\n<div id=\"fs-id1165137784178\">\r\n<p id=\"fs-id1165137784180\">35. [latex]|\\frac{3}{4}x-5|\\ge 7[\/latex]<\/p>\r\n\r\n<\/div>\r\n<div id=\"fs-id1165135377121\">[reveal-answer q=\"fs-id1165135377121\"]Show Solution[\/reveal-answer]\r\n[hidden-answer a=\"fs-id1165135377121\"]\r\n<p id=\"fs-id1165135377124\">[latex]\\left(-\\infty ,-\\frac{8}{3}\\right]\\cup \\left[16,\\infty \\right)[\/latex]<\/p>\r\n[\/hidden-answer]\r\n\r\n<\/div>\r\n<\/div>\r\n<div id=\"fs-id1165137419461\">\r\n<div id=\"fs-id1165137410039\">\r\n<p id=\"fs-id1165137410042\">36. [latex]|\\frac{3}{4}x-5|+1\\le 16[\/latex]<\/p>\r\n\r\n<\/div>\r\n<\/div>\r\n<\/div>\r\n<div class=\"bc-section section\">\r\n<h4>Graphical<\/h4>\r\n<p id=\"fs-id1165133047532\">For the following exercises, graph the absolute value function. Plot at least five points by hand for each graph.<\/p>\r\n\r\n<div id=\"fs-id1165137891404\">\r\n<div id=\"fs-id1165137817696\">\r\n<p id=\"fs-id1165137817699\">37. [latex]y=|x-1|[\/latex]<\/p>\r\n\r\n<\/div>\r\n<div><span id=\"fs-id1165135499906\">\r\n[reveal-answer q=\"601067\"]Show Solution[\/reveal-answer]\r\n[hidden-answer a=\"601067\"]<img class=\"aligncenter\" src=\"https:\/\/s3-us-west-2.amazonaws.com\/courses-images\/wp-content\/uploads\/sites\/3896\/2019\/02\/08205957\/CNX_Precalc_Figure_01_06_201.jpg\" alt=\"Graph of an absolute function with points at (-1, 2), (0, 1), (1, 0), (2, 1), and (3, 2).\" \/>[\/hidden-answer]<\/span><\/div>\r\n<\/div>\r\n<div id=\"fs-id1165137679099\">\r\n<div id=\"fs-id1165137679101\">\r\n<p id=\"fs-id1165137418760\">38. [latex]y=|x+1|[\/latex]<\/p>\r\n\r\n<\/div>\r\n<\/div>\r\n<div id=\"fs-id1165135422938\">\r\n<div id=\"fs-id1165135422940\">\r\n<p id=\"fs-id1165137652979\">39. [latex]y=|x|+1[\/latex]<\/p>\r\n\r\n<\/div>\r\n<div id=\"fs-id1165137414774\">[reveal-answer q=\"fs-id1165137414774\"]Show Solution[\/reveal-answer]\r\n[hidden-answer a=\"fs-id1165137414774\"]<span id=\"fs-id1165137658298\"><img class=\"aligncenter\" src=\"https:\/\/s3-us-west-2.amazonaws.com\/courses-images\/wp-content\/uploads\/sites\/3896\/2019\/02\/08205959\/CNX_Precalc_Figure_01_06_203.jpg\" alt=\"Graph of an absolute function with points at (-2, 3), (-1, 2), (0, 1), (1, 2), and (2, 3).\" \/><\/span>[\/hidden-answer]<\/div>\r\n<\/div>\r\n<p id=\"fs-id1165137406944\">For the following exercises, graph the given functions by hand.<\/p>\r\n\r\n<div id=\"fs-id1165135332726\">\r\n<div id=\"fs-id1165135332729\">\r\n<p id=\"fs-id1165135251459\">40. [latex]y=|x|-2[\/latex]<\/p>\r\n\r\n<\/div>\r\n<\/div>\r\n<div id=\"fs-id1165137601710\">\r\n<div id=\"fs-id1165137601713\">\r\n<p id=\"fs-id1165137419974\">41. [latex]y=-|x|[\/latex]<\/p>\r\n\r\n<\/div>\r\n<div id=\"fs-id1165137400044\">[reveal-answer q=\"fs-id1165137400044\"]Show Solution[\/reveal-answer]\r\n[hidden-answer a=\"fs-id1165137400044\"]<span id=\"fs-id1165135160170\"><img class=\"aligncenter\" src=\"https:\/\/s3-us-west-2.amazonaws.com\/courses-images\/wp-content\/uploads\/sites\/3896\/2019\/02\/08210002\/CNX_Precalc_Figure_01_06_205.jpg\" alt=\"Graph of an absolute function.\" \/><\/span>[\/hidden-answer]<\/div>\r\n<\/div>\r\n<div id=\"fs-id1165137735265\">\r\n<div id=\"fs-id1165137431347\">\r\n<p id=\"fs-id1165137431349\">42. [latex]y=-|x|-2[\/latex]<\/p>\r\n\r\n<\/div>\r\n<\/div>\r\n<div id=\"fs-id1165137731590\">\r\n<div id=\"fs-id1165137603675\">\r\n<p id=\"fs-id1165137603678\">43. [latex]y=-|x-3|-2[\/latex]<\/p>\r\n\r\n<\/div>\r\n<div id=\"fs-id1165137645253\">[reveal-answer q=\"fs-id1165137645253\"]Show Solution[\/reveal-answer]\r\n[hidden-answer a=\"fs-id1165137645253\"]<span id=\"fs-id1165135653964\"><img class=\"aligncenter\" src=\"https:\/\/s3-us-west-2.amazonaws.com\/courses-images\/wp-content\/uploads\/sites\/3896\/2019\/02\/08210004\/CNX_Precalc_Figure_01_06_207.jpg\" alt=\"Graph of an absolute function.\" \/><\/span>[\/hidden-answer]<\/div>\r\n<\/div>\r\n<div id=\"fs-id1165137394585\">\r\n<div id=\"fs-id1165137394587\">\r\n<p id=\"fs-id1165135572124\">44. [latex]f\\left(x\\right)=-|x-1|-2[\/latex]<\/p>\r\n\r\n<\/div>\r\n<\/div>\r\n<div id=\"fs-id1165135335986\">\r\n<div id=\"fs-id1165137651575\">\r\n<p id=\"fs-id1165137651578\">45. [latex]f\\left(x\\right)=-|x+3|+4[\/latex]<\/p>\r\n\r\n<\/div>\r\n<div id=\"fs-id1165137434149\">[reveal-answer q=\"fs-id1165137434149\"]Show Solution[\/reveal-answer]\r\n[hidden-answer a=\"fs-id1165137434149\"]<span id=\"fs-id1165137553071\"><img class=\"aligncenter\" src=\"https:\/\/s3-us-west-2.amazonaws.com\/courses-images\/wp-content\/uploads\/sites\/3896\/2019\/02\/08210006\/CNX_Precalc_Figure_01_06_209.jpg\" alt=\"Graph of an absolute function.\" \/><\/span>[\/hidden-answer]<\/div>\r\n<\/div>\r\n<div id=\"fs-id1165137705796\">\r\n<div id=\"fs-id1165137705798\">\r\n<p id=\"fs-id1165137469167\">46. [latex]f\\left(x\\right)=2|x+3|+1[\/latex]<\/p>\r\n\r\n<\/div>\r\n<\/div>\r\n<div id=\"fs-id1165137427199\">\r\n<div id=\"fs-id1165137619904\">\r\n<p id=\"fs-id1165137619906\">47. [latex]f\\left(x\\right)=3|x-2|+3[\/latex]<\/p>\r\n\r\n<\/div>\r\n<div id=\"fs-id1165137436399\">[reveal-answer q=\"fs-id1165137436399\"]Show Solution[\/reveal-answer]\r\n[hidden-answer a=\"fs-id1165137436399\"]<span id=\"fs-id1165137410325\"><img class=\"aligncenter\" src=\"https:\/\/s3-us-west-2.amazonaws.com\/courses-images\/wp-content\/uploads\/sites\/3896\/2019\/02\/08210009\/CNX_Precalc_Figure_01_06_211.jpg\" alt=\"Graph of an absolute function.\" \/><\/span>[\/hidden-answer]<\/div>\r\n<\/div>\r\n<div id=\"fs-id1165137715460\">\r\n<div id=\"fs-id1165137715462\">\r\n<p id=\"fs-id1165137469722\">48. [latex]f\\left(x\\right)=|2x-4|-3[\/latex]<\/p>\r\n\r\n<\/div>\r\n<\/div>\r\n<div id=\"fs-id1165135258293\">\r\n<div id=\"fs-id1165135258295\">\r\n<p id=\"fs-id1165137452029\">49. [latex]f\\left(x\\right)=|3x+9|+2[\/latex]<\/p>\r\n\r\n<\/div>\r\n<div id=\"fs-id1165137433126\">[reveal-answer q=\"fs-id1165137433126\"]Show Solution[\/reveal-answer]\r\n[hidden-answer a=\"fs-id1165137433126\"]<img class=\"aligncenter\" src=\"https:\/\/s3-us-west-2.amazonaws.com\/courses-images\/wp-content\/uploads\/sites\/3896\/2019\/02\/08210011\/CNX_Precalc_Figure_01_06_213.jpg\" alt=\"Graph of an absolute function.\" \/>[\/hidden-answer]<\/div>\r\n<\/div>\r\n<div id=\"fs-id1165137464095\">\r\n<div id=\"fs-id1165137464097\">\r\n<p id=\"fs-id1165137470140\">50. [latex]f\\left(x\\right)=-|x-1|-3[\/latex]<\/p>\r\n\r\n<\/div>\r\n<\/div>\r\n<div id=\"fs-id1165137443657\">\r\n<div id=\"fs-id1165137911316\">\r\n<p id=\"fs-id1165137911318\">51. [latex]f\\left(x\\right)=-|x+4|-3[\/latex]<\/p>\r\n\r\n<\/div>\r\n<div id=\"fs-id1165137399944\">[reveal-answer q=\"fs-id1165137399944\"]Show Solution[\/reveal-answer]\r\n[hidden-answer a=\"fs-id1165137399944\"]<span id=\"fs-id1165137451010\"><img class=\"aligncenter\" src=\"https:\/\/s3-us-west-2.amazonaws.com\/courses-images\/wp-content\/uploads\/sites\/3896\/2019\/02\/08210013\/CNX_Precalc_Figure_01_06_215.jpg\" alt=\"Graph of an absolute function.\" \/><\/span>[\/hidden-answer]<\/div>\r\n<\/div>\r\n<div id=\"fs-id1165137803326\">\r\n<div id=\"fs-id1165137803328\">\r\n<p id=\"fs-id1165137824374\">52. [latex]f\\left(x\\right)=\\frac{1}{2}|x+4|-3[\/latex]<\/p>\r\n\r\n<\/div>\r\n<\/div>\r\n<\/div>\r\n<div id=\"fs-id1165137897208\" class=\"bc-section section\">\r\n<h4>Technology<\/h4>\r\n<div id=\"fs-id1165137749758\">\r\n<div id=\"fs-id1165137749760\">\r\n<p id=\"fs-id1165137460158\">53. Use a graphing utility to graph [latex]f\\left(x\\right)=10|x-2|[\/latex] on the viewing window [latex]\\left[0,4\\right].[\/latex] Identify the corresponding range. Show the graph.<\/p>\r\n\r\n<\/div>\r\n<div id=\"fs-id1165134042934\">[reveal-answer q=\"fs-id1165134042934\"]Show Solution[\/reveal-answer]\r\n[hidden-answer a=\"fs-id1165134042934\"]\r\n<p id=\"fs-id1165134042935\">range:[latex]\\text{ }\\left[0,20\\right][\/latex]<\/p>\r\n<img class=\"aligncenter\" src=\"https:\/\/s3-us-west-2.amazonaws.com\/courses-images\/wp-content\/uploads\/sites\/3896\/2019\/02\/08210015\/CNX_Precalc_Figure_01_06_217.jpg\" alt=\"Graph of an absolute function.\" \/>[\/hidden-answer]\r\n\r\n<\/div>\r\n<\/div>\r\n<div id=\"fs-id1165137413783\">\r\n<div id=\"fs-id1165137434783\">\r\n<p id=\"fs-id1165137434785\">54. Use a graphing utility to graph[latex]\\text{ }f\\left(x\\right)=-100|x|+100\\text{ }[\/latex]on the viewing window[latex]\\text{ }\\left[-5,5\\right].\\text{ }[\/latex]Identify the corresponding range. Show the graph.<\/p>\r\n\r\n<\/div>\r\n<\/div>\r\n<p id=\"fs-id1165137831208\">For the following exercises, graph each function using a graphing utility. Specify the viewing window.<\/p>\r\n\r\n<div id=\"fs-id1165137762283\">\r\n<div id=\"fs-id1165135464843\">\r\n<p id=\"fs-id1165137724085\">55. [latex]f\\left(x\\right)=-0.1|0.1\\left(0.2-x\\right)|+0.3[\/latex]<\/p>\r\n\r\n<\/div>\r\n<div>\r\n\r\n[reveal-answer q=\"258236\"]Show Soution[\/reveal-answer]\r\n[hidden-answer a=\"258236\"]\r\n<p id=\"fs-id1165137812573\">[latex]x\\text{-}[\/latex]intercepts:<\/p>\r\n<span id=\"fs-id1165137784866\"><img class=\"aligncenter\" src=\"https:\/\/s3-us-west-2.amazonaws.com\/courses-images\/wp-content\/uploads\/sites\/3896\/2019\/02\/08210018\/CNX_Precalc_Figure_01_06_219.jpg\" alt=\"Graph of an absolute function.\" \/><\/span>\r\n\r\n[\/hidden-answer]\r\n\r\n<\/div>\r\n<\/div>\r\n<div id=\"eip-id1165134039354\">\r\n<div id=\"eip-id1165134039356\">\r\n<p id=\"fs-id1165137483195\">56. [latex]f\\left(x\\right)=4\u00d7{10}^{9}|x-\\left(5\u00d7{10}^{9}\\right)|+2\u00d7{10}^{9}[\/latex]<\/p>\r\n\r\n<\/div>\r\n<\/div>\r\n<\/div>\r\n<div id=\"fs-id1165137419467\" class=\"bc-section section\">\r\n<h4>Extensions<\/h4>\r\n<p id=\"fs-id1165137901338\">For the following exercises, solve the inequality.<\/p>\r\n\r\n<div id=\"fs-id1165137901341\">\r\n<div id=\"fs-id1165135397245\">\r\n<p id=\"fs-id1165135397247\">57. [latex]|-2x-\\frac{2}{3}\\left(x+1\\right)|+3&gt;-1[\/latex]<\/p>\r\n\r\n<\/div>\r\n<div id=\"fs-id1165137662699\">[reveal-answer q=\"fs-id1165137662699\"]Show Solution[\/reveal-answer]\r\n[hidden-answer a=\"fs-id1165137662699\"]\r\n<p id=\"fs-id1165137662701\">[latex]\\left(-\\infty ,\\infty \\right)[\/latex]<\/p>\r\n[\/hidden-answer]\r\n\r\n<\/div>\r\n<\/div>\r\n<div id=\"fs-id1165137434569\">\r\n<div id=\"fs-id1165137434570\">\r\n<p id=\"fs-id1165137434571\">58. If possible, find all values of [latex]a[\/latex] such that there are no [latex]x\\text{-}[\/latex]intercepts for [latex]f\\left(x\\right)=2|x+1|+a.[\/latex]<\/p>\r\n\r\n<\/div>\r\n<\/div>\r\n<div id=\"fs-id1165137639316\">\r\n<div id=\"fs-id1165137652958\">\r\n<p id=\"fs-id1165137652960\">59. If possible, find all values of[latex]\\text{ }a\\text{ }[\/latex]such that there are no [latex]\\text{ }y[\/latex]-intercepts for[latex]\\text{ }f\\left(x\\right)=2|x+1|+a.[\/latex]<\/p>\r\n\r\n<\/div>\r\n<div id=\"fs-id1165137648025\">[reveal-answer q=\"fs-id1165137648025\"]Show Solution[\/reveal-answer]\r\n[hidden-answer a=\"fs-id1165137648025\"]\r\n<p id=\"fs-id1165137454792\">There is no solution for[latex]\\text{ }a\\text{ }[\/latex]that will keep the function from having a[latex]\\text{ }y[\/latex]-intercept. The absolute value function always crosses the [latex]\\text{ }y[\/latex]-intercept when[latex]\\text{ }x=0.[\/latex]<\/p>\r\n[\/hidden-answer]\r\n\r\n<\/div>\r\n<\/div>\r\n<\/div>\r\n<div id=\"fs-id1165135172151\" class=\"bc-section section\">\r\n<h4>Real-World Applications<\/h4>\r\n<div id=\"fs-id1165137641899\">\r\n<div id=\"fs-id1165137641901\">\r\n<p id=\"fs-id1165137459748\">60. Cities A and B are on the same east-west line. Assume that city A is located at the origin. If the distance from city A to city B is at least 100 miles and[latex]\\text{ }x\\text{ }[\/latex]represents the distance from city B to city A, express this using absolute value notation.<\/p>\r\n\r\n<\/div>\r\n<\/div>\r\n<div id=\"fs-id1165137812302\">\r\n<div id=\"fs-id1165137812304\">\r\n<p id=\"fs-id1165137431941\">61. The true proportion[latex]\\text{ }p\\text{ }[\/latex]of people who give a favorable rating to Congress is 8% with a margin of error of 1.5%. Describe this statement using an absolute value equation.<\/p>\r\n\r\n<\/div>\r\n<div id=\"fs-id1165135431083\">[reveal-answer q=\"fs-id1165135431083\"]Show Solution[\/reveal-answer]\r\n[hidden-answer a=\"fs-id1165135431083\"]\r\n<p id=\"fs-id1165134042456\">[latex]|p-0.08|\\le 0.015[\/latex]<\/p>\r\n[\/hidden-answer]\r\n\r\n<\/div>\r\n<\/div>\r\n<div id=\"fs-id1165137598001\">\r\n<div id=\"fs-id1165137562568\">\r\n<p id=\"fs-id1165137562570\">62. Students who score within 18 points of the number 82 will pass a particular test. Write this statement using absolute value notation and use the variable[latex]\\text{ }x\\text{ }[\/latex]for the score.<\/p>\r\n\r\n<\/div>\r\n<\/div>\r\n<div id=\"fs-id1165137758810\">\r\n<div id=\"fs-id1165137758812\">\r\n<p id=\"fs-id1165135332394\">63. A machinist must produce a bearing that is within 0.01 inches of the correct diameter of 5.0 inches. Using[latex]\\text{ }x\\text{ }[\/latex]as the diameter of the bearing, write this statement using absolute value notation.<\/p>\r\n\r\n<\/div>\r\n<div id=\"fs-id1165135192953\">[reveal-answer q=\"fs-id1165135192953\"]Show Solution[\/reveal-answer]\r\n[hidden-answer a=\"fs-id1165135192953\"][latex]|x-5.0|\\le 0.01[\/latex][\/hidden-answer]<\/div>\r\n<\/div>\r\n<div id=\"fs-id1165137732323\">\r\n<div id=\"fs-id1165137732325\">\r\n<p id=\"fs-id1165137673610\">64. The tolerance for a ball bearing is 0.01. If the true diameter of the bearing is to be 2.0 inches and the measured value of the diameter is[latex]\\text{ }x\\text{ }[\/latex]inches, express the tolerance using absolute value notation.<\/p>\r\n\r\n<\/div>\r\n<\/div>\r\n<\/div>\r\n<\/div>\r\n<div class=\"textbox shaded\">\r\n<h3>Glossary<\/h3>\r\n<dl id=\"fs-id1165135191341\">\r\n \t<dt>absolute value equation<\/dt>\r\n \t<dd id=\"fs-id1165137627032\">an equation of the form[latex]\\text{ }|A|=B,\\text{ }[\/latex]with[latex]\\text{ }B\\ge 0;\\text{ }[\/latex]it will have solutions when[latex]\\text{ }A=B\\text{ }[\/latex]or[latex]\\text{ }A=-B[\/latex]<\/dd>\r\n<\/dl>\r\n<dl id=\"fs-id1165137560214\">\r\n \t<dt>absolute value inequality<\/dt>\r\n \t<dd id=\"fs-id1165135173524\">a relationship in the form[latex]|A|&lt;B,\\text{ }\\text{ }\\text{ }|A|\\le B,\\text{ }\\text{ }\\text{ }\\text{ }|A|&gt;B,\\text{ }\\text{ }\\text{or }\\text{ }\\text{ }|A|\\ge B[\/latex]<\/dd>\r\n<\/dl>\r\n<\/div>","rendered":"<div class=\"textbox learning-objectives\">\n<h3>Learning Objectives<\/h3>\n<p>In this section you will:<\/p>\n<ul>\n<li>Graph an absolute value function.<\/li>\n<li>Solve an absolute value equation.<\/li>\n<li>Solve an absolute value inequality.<\/li>\n<\/ul>\n<\/div>\n<div id=\"Figure_01_06_001\" class=\"medium\">\n<div style=\"width: 498px\" class=\"wp-caption aligncenter\"><img loading=\"lazy\" decoding=\"async\" src=\"https:\/\/s3-us-west-2.amazonaws.com\/courses-images\/wp-content\/uploads\/sites\/3896\/2019\/02\/08205917\/CNX_Precalc_Figure_01_06_001n.jpg\" alt=\"The Milky Way.\" width=\"488\" height=\"338\" \/><\/p>\n<p class=\"wp-caption-text\"><strong>Figure 1.\u00a0<\/strong>Distances in deep space can be measured in all directions. As such, it is useful to consider distance in terms of absolute values. (credit: &#8220;s58y&#8221;\/Flickr)<\/p>\n<\/div>\n<\/div>\n<p id=\"fs-id1165137475222\">Until the 1920s, the so-called spiral nebulae were believed to be clouds of dust and gas in our own galaxy, some tens of thousands of light years away. Then, astronomer Edwin Hubble proved that these objects are galaxies in their own right, at distances of millions of light years. Today, astronomers can detect galaxies that are billions of light years away. Distances in the universe can be measured in all directions. As such, it is useful to consider distance as an absolute value function. In this section, we will investigate <strong><span class=\"no-emphasis\">absolute value functions<\/span><\/strong>.<\/p>\n<div id=\"fs-id1165137426078\" class=\"bc-section section\">\n<h3>Understanding Absolute Value<\/h3>\n<p id=\"fs-id1165135449691\">Recall that in its basic form[latex]\\text{ }f\\left(x\\right)=|x|,\\text{ }[\/latex]the <strong>absolute value<\/strong> function, is one of our toolkit functions. The <span class=\"no-emphasis\">absolute value<\/span> function is commonly thought of as providing the distance the number is from zero on a number line. Algebraically, for whatever the input value is, the output is the value without regard to sign.<\/p>\n<div id=\"fs-id1165135404116\">\n<div class=\"textbox shaded\">\n<h3>Absolute Value Function<\/h3>\n<p id=\"fs-id1165137832269\">The absolute value function can be defined as a piecewise function<\/p>\n<div id=\"fs-id1165137665354\" class=\"unnumbered\" style=\"text-align: center\">[latex]\\text{ }f\\left(x\\right)=|x|=\\bigg\\{\\begin{array}{ccc}x& \\text{if}& x\\ge 0\\\\ -x& \\text{if}& x<0\\end{array}\\text{ }[\/latex]<\/div>\n<\/div>\n<\/div>\n<div id=\"Example_01_06_01\" class=\"textbox examples\">\n<div id=\"fs-id1165137437173\">\n<div id=\"fs-id1165137618976\">\n<h3>Example 1: Determine a Number within a Prescribed Distance<\/h3>\n<p id=\"fs-id1165137761508\">Describe all values[latex]\\text{ }x\\text{ }[\/latex]within or including a distance of 4 from the number 5.<\/p>\n<\/div>\n<div id=\"fs-id1165135193649\">\n<div class=\"qa-wrapper\" style=\"display: block\"><span class=\"show-answer collapsed\" style=\"cursor: pointer\" data-target=\"qfs-id1165135193649\">Show Solution<\/span><\/p>\n<div id=\"qfs-id1165135193649\" class=\"hidden-answer\" style=\"display: none\">\n<p id=\"fs-id1165135424674\">We want the distance between[latex]\\text{ }x\\text{ }[\/latex]and 5 to be less than or equal to 4. We can draw a number line, such as the one in <a class=\"autogenerated-content\" href=\"#Figure_01_06_002\">(Figure)<\/a>, to represent the condition to be satisfied.<\/p>\n<div id=\"Figure_01_06_002\" class=\"small\">\n<div style=\"width: 497px\" class=\"wp-caption aligncenter\"><img loading=\"lazy\" decoding=\"async\" src=\"https:\/\/s3-us-west-2.amazonaws.com\/courses-images\/wp-content\/uploads\/sites\/3896\/2019\/02\/08205924\/CNX_Precalc_Figure_01_06_002.jpg\" alt=\"Number line describing the difference of the distance of 4 away from 5.\" width=\"487\" height=\"81\" \/><\/p>\n<p class=\"wp-caption-text\"><strong>Figure 2.<\/strong><\/p>\n<\/div>\n<\/div>\n<p id=\"fs-id1165137772130\">The distance from[latex]\\text{ }x\\text{ }[\/latex]to 5 can be represented using the absolute value as[latex]\\text{ }|x-5|.\\text{ }[\/latex]We want the values of[latex]\\text{ }x\\text{ }[\/latex]that satisfy the condition [latex]|x-5|\\le 4.[\/latex]<\/p>\n<\/div>\n<\/div>\n<\/div>\n<div id=\"fs-id1165137656116\">\n<h3>Analysis<\/h3>\n<p id=\"fs-id1165135161478\">Note that<\/p>\n<div id=\"fs-id1165134394601\" class=\"unnumbered\" style=\"text-align: center\">[latex]\\begin{array}{lll}-4\\le x-5\\hfill & \\begin{array}{ccc}& & \\end{array}\\hfill & x-5\\le 4\\hfill \\\\ \\text{ }\\text{ }\\text{ }\\text{ }1\\le x\\hfill & \\hfill & \\text{ }\\text{ }\\text{ }\\text{ }\\text{ }\\text{ }\\text{ }\\text{ }\\text{ }\\text{ }x\\le 9\\hfill \\end{array}[\/latex]<\/div>\n<p id=\"fs-id1165137569650\">So[latex]\\text{ }|x-5|\\le 4\\text{ }[\/latex]is equivalent to[latex]\\text{ }1\\le x\\le 9.[\/latex]<\/p>\n<p id=\"fs-id1165137539782\">However, mathematicians generally prefer absolute value notation.<\/p>\n<\/div>\n<\/div>\n<\/div>\n<div id=\"fs-id1165137408957\" class=\"precalculus tryit\">\n<h3>Try it #1<\/h3>\n<div id=\"ti_01_06_01\">\n<div id=\"fs-id1165135394308\">\n<p id=\"fs-id1165135394310\">Describe all values[latex]\\text{ }x\\text{ }[\/latex]within a distance of 3 from the number 2.<\/p>\n<\/div>\n<div id=\"fs-id1165135160738\">\n<div class=\"qa-wrapper\" style=\"display: block\"><span class=\"show-answer collapsed\" style=\"cursor: pointer\" data-target=\"qfs-id1165135160738\">Show Solution<\/span><\/p>\n<div id=\"qfs-id1165135160738\" class=\"hidden-answer\" style=\"display: none\">\n<p id=\"fs-id1165135160739\">[latex]|x-2|\\le 3[\/latex]<\/p>\n<\/div>\n<\/div>\n<\/div>\n<\/div>\n<\/div>\n<div id=\"Example_01_06_02\" class=\"textbox examples\">\n<div id=\"fs-id1165137657277\">\n<div id=\"fs-id1165137579723\">\n<h3>Example 2: Resistance of a Resistor<\/h3>\n<p id=\"fs-id1165135203760\">Electrical parts, such as resistors and capacitors, come with specified values of their operating parameters: resistance, capacitance, etc. However, due to imprecision in manufacturing, the actual values of these parameters vary somewhat from piece to piece, even when they are supposed to be the same. The best that manufacturers can do is to try to guarantee that the variations will stay within a specified range, often[latex]\\text{ }\\text{\u00b11%,}\\text{ }\u00b1\\text{5%,}\\text{ }[\/latex]or[latex]\\text{ }\u00b1\\text{10%}\\text{.}[\/latex]<\/p>\n<p id=\"fs-id1165135175007\">Suppose we have a resistor rated at 680 ohms,[latex]\\text{ }\u00b15%.\\text{ }[\/latex]Use the absolute value function to express the range of possible values of the actual resistance.<\/p>\n<\/div>\n<div id=\"fs-id1165137786481\">\n<div class=\"qa-wrapper\" style=\"display: block\"><span class=\"show-answer collapsed\" style=\"cursor: pointer\" data-target=\"qfs-id1165137786481\">Show Solution<\/span><\/p>\n<div id=\"qfs-id1165137786481\" class=\"hidden-answer\" style=\"display: none\">\n<p id=\"fs-id1165137600783\">5% of 680 ohms is 34 ohms. The absolute value of the difference between the actual and nominal resistance should not exceed the stated variability, so, with the resistance[latex]\\text{ }R\\text{ }[\/latex]in ohms,<\/p>\n<div id=\"fs-id1165135176481\" class=\"unnumbered\" style=\"text-align: center\">[latex]|R-680|\\le 34[\/latex]<\/div>\n<\/div>\n<\/div>\n<\/div>\n<\/div>\n<\/div>\n<div id=\"fs-id1165137540249\" class=\"precalculus tryit\">\n<h3>Try it #2<\/h3>\n<div id=\"ti_01_06_02\">\n<div id=\"fs-id1165137828265\">\n<p id=\"fs-id1165137828266\">Students who score within 20 points of 80 will pass a test. Write this as a distance from 80 using absolute value notation.<\/p>\n<\/div>\n<div id=\"fs-id1165137715310\">\n<div class=\"qa-wrapper\" style=\"display: block\"><span class=\"show-answer collapsed\" style=\"cursor: pointer\" data-target=\"qfs-id1165137715310\">Show Solution<\/span><\/p>\n<div id=\"qfs-id1165137715310\" class=\"hidden-answer\" style=\"display: none\">\n<p id=\"fs-id1165134090680\">using the variable[latex]\\text{ }p\\text{ }[\/latex]for passing,[latex]\\text{ }|p-80|\\le 20[\/latex]<\/p>\n<\/div>\n<\/div>\n<\/div>\n<\/div>\n<\/div>\n<\/div>\n<div id=\"fs-id1165135186288\" class=\"bc-section section\">\n<h3>Graphing an Absolute Value Function<\/h3>\n<p id=\"fs-id1165135570012\">The most significant feature of the absolute value graph is the corner point at which the graph changes direction. This point is shown at the <strong><span class=\"no-emphasis\">origin<\/span><\/strong> in <a class=\"autogenerated-content\" href=\"#Figure_01_06_003\">(Figure)<\/a>.<\/p>\n<div id=\"Figure_01_06_003\" class=\"small\">\n<div style=\"width: 497px\" class=\"wp-caption aligncenter\"><img loading=\"lazy\" decoding=\"async\" src=\"https:\/\/s3-us-west-2.amazonaws.com\/courses-images\/wp-content\/uploads\/sites\/3896\/2019\/02\/08205927\/CNX_Precalc_Figure_01_06_003.jpg\" alt=\"Graph of an absolute function\" width=\"487\" height=\"251\" \/><\/p>\n<p class=\"wp-caption-text\"><strong>Figure 3.<\/strong><\/p>\n<\/div>\n<\/div>\n<p id=\"fs-id1165135639350\"><a class=\"autogenerated-content\" href=\"#Figure_01_06_004\">(Figure)<\/a> shows the graph of[latex]\\text{ }y=2|x\u20133|+4.\\text{ }[\/latex]The graph of[latex]\\text{ }y=|x|\\text{ }[\/latex]has been shifted right 3 units, vertically stretched by a factor of 2, and shifted up 4 units. This means that the corner point is located at[latex]\\text{ }\\left(3,4\\right)\\text{ }[\/latex]for this transformed function.<\/p>\n<div id=\"Figure_01_06_004\" class=\"small\">\n<div style=\"width: 497px\" class=\"wp-caption aligncenter\"><img loading=\"lazy\" decoding=\"async\" src=\"https:\/\/s3-us-west-2.amazonaws.com\/courses-images\/wp-content\/uploads\/sites\/3896\/2019\/02\/08205930\/CNX_Precalc_Figure_01_06_004.jpg\" alt=\"Graph of the different types of transformations for an absolute function.\" width=\"487\" height=\"486\" \/><\/p>\n<p class=\"wp-caption-text\"><strong>Figure 4.<\/strong><\/p>\n<\/div>\n<\/div>\n<div id=\"Example_01_06_03\" class=\"textbox examples\">\n<div id=\"fs-id1165135187768\">\n<div id=\"fs-id1165137741094\">\n<h3>Example 3: Writing an Equation for an Absolute Value Function<\/h3>\n<p id=\"fs-id1165135414332\">Write an equation for the function graphed in <a class=\"autogenerated-content\" href=\"#Figure_01_06_005\">(Figure)<\/a>.<\/p>\n<div id=\"Figure_01_06_005\" class=\"small\">\n<div style=\"width: 497px\" class=\"wp-caption aligncenter\"><img loading=\"lazy\" decoding=\"async\" src=\"https:\/\/s3-us-west-2.amazonaws.com\/courses-images\/wp-content\/uploads\/sites\/3896\/2019\/02\/08205933\/CNX_Precalc_Figure_01_06_005.jpg\" alt=\"Graph of an absolute function.\" width=\"487\" height=\"363\" \/><\/p>\n<p class=\"wp-caption-text\"><strong>Figure 5.<\/strong><\/p>\n<\/div>\n<\/div>\n<\/div>\n<div id=\"fs-id1165137736321\">\n<div class=\"qa-wrapper\" style=\"display: block\"><span class=\"show-answer collapsed\" style=\"cursor: pointer\" data-target=\"qfs-id1165137736321\">Show Solution<\/span><\/p>\n<div id=\"qfs-id1165137736321\" class=\"hidden-answer\" style=\"display: none\">\n<p id=\"fs-id1165137680556\">The basic absolute value function changes direction at the origin, so this graph has been shifted to the right 3 units and down 2 units from the basic toolkit function. See <a class=\"autogenerated-content\" href=\"#Figure_01_06_006\">(Figure)<\/a>.<\/p>\n<div id=\"Figure_01_06_006\" class=\"small\">\n<div style=\"width: 497px\" class=\"wp-caption aligncenter\"><img loading=\"lazy\" decoding=\"async\" src=\"https:\/\/s3-us-west-2.amazonaws.com\/courses-images\/wp-content\/uploads\/sites\/3896\/2019\/02\/08205936\/CNX_Precalc_Figure_01_06_006.jpg\" alt=\"Graph of two transformations for an absolute function at (3, -2).\" width=\"487\" height=\"363\" \/><\/p>\n<p class=\"wp-caption-text\"><strong>Figure 6.<\/strong><\/p>\n<\/div>\n<\/div>\n<p id=\"fs-id1165137805107\">We also notice that the graph appears vertically stretched, because the width of the final graph on a horizontal line is not equal to 2 times the vertical distance from the corner to this line, as it would be for an unstretched absolute value function. Instead, the width is equal to 1 times the vertical distance as shown in <a class=\"autogenerated-content\" href=\"#Figure_01_06_007\">(Figure)<\/a>.<\/p>\n<div id=\"Figure_01_06_007\" class=\"small\">\n<div style=\"width: 497px\" class=\"wp-caption aligncenter\"><img loading=\"lazy\" decoding=\"async\" src=\"https:\/\/s3-us-west-2.amazonaws.com\/courses-images\/wp-content\/uploads\/sites\/3896\/2019\/02\/08205939\/CNX_Precalc_Figure_01_06_007.jpg\" alt=\"Graph of two transformations for an absolute function at (3, -2) and describes the ratios between the two different transformations.\" width=\"487\" height=\"363\" \/><\/p>\n<p class=\"wp-caption-text\"><strong>Figure 7.<\/strong><\/p>\n<\/div>\n<\/div>\n<p id=\"fs-id1165137732766\">From this information we can write the equation<\/p>\n<div id=\"fs-id1165137425569\" class=\"unnumbered\" style=\"text-align: center\">[latex]\\begin{array}{ll}f\\left(x\\right)=2|x-3|-2,\\hfill & \\text{treating the stretch as a vertical stretch, or}\\hfill \\\\ f\\left(x\\right)=|2\\left(x-3\\right)|-2,\\hfill & \\text{treating the stretch as a horizontal compression}.\\hfill \\end{array}[\/latex]<\/div>\n<\/div>\n<\/div>\n<\/div>\n<div id=\"fs-id1165137706602\">\n<h3>Analysis<\/h3>\n<p id=\"fs-id1165137591631\">Note that these equations are algebraically equivalent\u2014the stretch for an absolute value function can be written interchangeably as a vertical or horizontal stretch or compression.<\/p>\n<\/div>\n<\/div>\n<\/div>\n<div id=\"fs-id1165134377948\" class=\"precalculus qa key-takeaways\">\n<h3>Q&amp;A<\/h3>\n<p id=\"fs-id1165135245777\"><strong>If we couldn\u2019t observe the stretch of the function from the graphs, could we algebraically determine it?<\/strong><\/p>\n<p id=\"fs-id1165137473393\"><em>Yes. If we are unable to determine the stretch based on the width of the graph, we can solve for the stretch factor by putting in a known pair of values for[latex]\\text{ }x\\text{ }[\/latex]and[latex]\\text{ }f\\left(x\\right).[\/latex] <\/em><\/p>\n<div id=\"fs-id1165135514699\" class=\"unnumbered\" style=\"text-align: center\">[latex]f\\left(x\\right)=a|x-3|-2[\/latex]<\/div>\n<p id=\"fs-id1165137694034\"><em>Now substituting in the point <\/em>(1, 2)<\/p>\n<div id=\"fs-id1165135173265\" class=\"unnumbered\" style=\"text-align: center\">[latex]\\begin{array}{l}2=a|1-3|-2\\hfill \\\\ 4=2a\\hfill \\\\ a=2\\hfill \\end{array}[\/latex]<\/div>\n<\/div>\n<div id=\"fs-id1165137611709\" class=\"precalculus tryit\">\n<h3>Try it #3<\/h3>\n<div id=\"ti_01_06_03\">\n<div id=\"fs-id1165134312222\">\n<p id=\"fs-id1165135497155\">Write the equation for the absolute value function that is horizontally shifted left 2 units, is vertically flipped, and vertically shifted up 3 units.<\/p>\n<\/div>\n<div id=\"fs-id1165137405204\">\n<div class=\"qa-wrapper\" style=\"display: block\"><span class=\"show-answer collapsed\" style=\"cursor: pointer\" data-target=\"qfs-id1165137405204\">Show Solution<\/span><\/p>\n<div id=\"qfs-id1165137405204\" class=\"hidden-answer\" style=\"display: none\">\n<p id=\"fs-id1165137758260\">[latex]f\\left(x\\right)=-|x+2|+3[\/latex]<\/p>\n<\/div>\n<\/div>\n<\/div>\n<\/div>\n<\/div>\n<div id=\"fs-id1165135203778\" class=\"precalculus qa key-takeaways\">\n<h3>Q&amp;A<\/h3>\n<p id=\"fs-id1165137527840\"><strong>Do the graphs of absolute value functions always intersect the vertical axis? The horizontal axis? <\/strong><\/p>\n<p id=\"fs-id1165137581861\"><em>Yes, they always intersect the vertical axis. The graph of an absolute value function will intersect the vertical axis when the input is zero. <\/em><\/p>\n<p id=\"fs-id1165137444543\"><em>No, they do not always intersect the horizontal axis. The graph may or may not intersect the horizontal axis, depending on how the graph has been shifted and reflected. It is possible for the absolute value function to intersect the horizontal axis at zero, one, or two points (see <a class=\"autogenerated-content\" href=\"#Figure_01_06_008\">(Figure)<\/a>). <\/em><\/p>\n<\/div>\n<div id=\"Figure_01_06_008\" class=\"wp-caption aligncenter\">\n<div style=\"width: 985px\" class=\"wp-caption aligncenter\"><img loading=\"lazy\" decoding=\"async\" src=\"https:\/\/s3-us-west-2.amazonaws.com\/courses-images\/wp-content\/uploads\/sites\/3896\/2019\/02\/08205943\/CNX_Precalc_Figure_01_06_008abc.jpg\" alt=\"Graph of the different types of transformations for an absolute function.\" width=\"975\" height=\"415\" \/><\/p>\n<p class=\"wp-caption-text\"><strong>Figure 8.\u00a0<\/strong>(a) The absolute value function does not intersect the horizontal axis. (b) The absolute value function intersects the horizontal axis at one point. (c) The absolute value function intersects the horizontal axis at two points.<\/p>\n<\/div>\n<\/div>\n<div class=\"wp-caption-text\"><\/div>\n<\/div>\n<div id=\"fs-id1165133257286\" class=\"bc-section section\">\n<h3>Solving an Absolute Value Equation<\/h3>\n<p id=\"fs-id1165137401775\">Now that we can graph an absolute value function, we will learn how to solve an absolute value equation. To solve an equation such as[latex]\\text{ }8=|2x-6|,\\text{ }[\/latex]we notice that the absolute value will be equal to 8 if the quantity inside the absolute value is 8 or -8. This leads to two different equations we can solve independently.<\/p>\n<div id=\"fs-id1165137583696\" class=\"unnumbered\" style=\"text-align: center\">[latex]\\begin{array}{lll}2x-6=8\\hfill & \\text{or}\\hfill & 2x-6=-8\\hfill \\\\ \\text{ }\\text{ }\\text{ }\\text{ }\\text{ }\\text{ }\\text{ }\\text{ }2x=14\\hfill & \\hfill & \\text{ }\\text{ }\\text{ }\\text{ }\\text{ }\\text{ }\\text{ }\\text{ }\\text{ }2x=-2\\hfill \\\\ \\text{ }\\text{ }\\text{ }\\text{ }\\text{ }\\text{ }\\text{ }\\text{ }\\text{ }\\text{ }\\text{ }x=7\\hfill & \\hfill & \\text{ }\\text{ }\\text{ }\\text{ }\\text{ }\\text{ }\\text{ }\\text{ }\\text{ }\\text{ }\\text{ }\\text{ }x=-1\\hfill \\end{array}[\/latex]<\/div>\n<p id=\"fs-id1165137641126\">Knowing how to solve problems involving <strong><span class=\"no-emphasis\">absolute value functions<\/span><\/strong> is useful. For example, we may need to identify numbers or points on a line that are at a specified distance from a given reference point.<\/p>\n<p>An <strong>absolute value equation<\/strong> is an equation in which the unknown variable appears in absolute value bars. For example,<\/p>\n<div id=\"fs-id1165137646929\" class=\"unnumbered\" style=\"text-align: center\">[latex]\\begin{array}{l}|x|=4,\\hfill \\\\ |2x-1|=3\\hfill \\\\ |5x+2|-4=9\\hfill \\end{array}[\/latex]<\/div>\n<div id=\"fs-id1165137692078\">\n<div class=\"textbox shaded\">\n<h3>Solutions to Absolute Value Equations<\/h3>\n<p id=\"fs-id1165137809877\">For real numbers[latex]\\text{ }A\\text{ }[\/latex]and[latex]\\text{ }B,\\text{ }[\/latex]an equation of the form[latex]\\text{ }|A|=B,\\text{ }[\/latex]with[latex]\\text{ }B\\ge 0,\\text{ }[\/latex]will have solutions when[latex]\\text{ }A=B\\text{ }[\/latex]or[latex]\\text{ }A=-B.\\text{ }[\/latex]If[latex]\\text{ }B<0,\\text{ }[\/latex]the equation[latex]\\text{ }|A|=B\\text{ }[\/latex]has no solution.<\/p>\n<\/div>\n<\/div>\n<div id=\"fs-id1165135160087\" class=\"precalculus howto examples\">\n<h3>How To<\/h3>\n<p id=\"fs-id1165135593248\"><strong>Given the formula for an absolute value function, find the horizontal intercepts of its graph<\/strong>.<\/p>\n<ol id=\"fs-id1165131968095\" type=\"1\">\n<li>Isolate the absolute value term.<\/li>\n<li>Use[latex]\\text{ }|A|=B\\text{ }[\/latex]to write[latex]\\text{ }A=B\\text{ }[\/latex]or[latex]\\text{ }\\mathrm{-A}=B,\\text{ }[\/latex]assuming[latex]\\text{ }B>0.[\/latex]<\/li>\n<li>Solve for[latex]\\text{ }x.\\text{ }[\/latex]<\/li>\n<\/ol>\n<\/div>\n<div id=\"Example_01_06_04\" class=\"textbox examples\">\n<div id=\"fs-id1165137619575\">\n<div id=\"fs-id1165135309797\">\n<h3>Example 4: Finding the Zeros of an Absolute Value Function<\/h3>\n<p id=\"fs-id1165137527684\">For the function[latex]\\text{ }f\\left(x\\right)=|4x+1|-7[\/latex], find the values of [latex]x[\/latex] such that [latex]\\text{ }f\\left(x\\right)=0[\/latex].<\/p>\n<\/div>\n<div id=\"fs-id1165137405662\">\n<div class=\"qa-wrapper\" style=\"display: block\"><span class=\"show-answer collapsed\" style=\"cursor: pointer\" data-target=\"qfs-id1165137405662\">Show Solution<\/span><\/p>\n<div id=\"qfs-id1165137405662\" class=\"hidden-answer\" style=\"display: none\">\n<div id=\"fs-id1165137618972\" class=\"unnumbered\" style=\"text-align: center\">[latex]\\begin{array}{lllllll}0=|4x+1|-7\\hfill & \\hfill & \\hfill & \\hfill & \\hfill & \\hfill & \\text{Substitute 0 for }f\\left(x\\right).\\hfill \\\\ 7=|4x+1|\\hfill & \\hfill & \\hfill & \\hfill & \\hfill & \\hfill & \\text{Isolate the absolute value on one side of the equation}.\\hfill \\\\ \\hfill & \\hfill & \\hfill & \\hfill & \\hfill & \\hfill & \\hfill \\\\ \\hfill & \\hfill & \\hfill & \\hfill & \\hfill & \\hfill & \\hfill \\\\ \\hfill & \\hfill & \\hfill & \\hfill & \\hfill & \\hfill & \\hfill \\\\ 7=4x+1\\hfill & \\text{or}\\hfill & \\hfill & \\hfill & \\hfill & -7=4x+1\\hfill & \\text{Break into two separate equations and solve}.\\hfill \\\\ 6=4x\\hfill & \\hfill & \\hfill & \\hfill & \\hfill & -8=4x\\hfill & \\hfill \\\\ \\hfill & \\hfill & \\hfill & \\hfill & \\hfill & \\hfill & \\hfill \\\\ x=\\frac{6}{4}=1.5\\hfill & \\hfill & \\hfill & \\hfill & \\hfill & \\text{ }x=\\frac{-8}{4}=-2\\hfill & \\hfill \\end{array}[\/latex]<\/div>\n<p id=\"fs-id1165137870931\">The function outputs 0 when[latex]\\text{ }x=1.5\\text{ }[\/latex]or[latex]\\text{ }x=-2.[\/latex] See <a class=\"autogenerated-content\" href=\"#Figure_01_06_011\">(Figure)<\/a>.<\/p>\n<div id=\"Figure_01_06_011\" class=\"medium\">\n<div style=\"width: 741px\" class=\"wp-caption aligncenter\"><img loading=\"lazy\" decoding=\"async\" src=\"https:\/\/s3-us-west-2.amazonaws.com\/courses-images\/wp-content\/uploads\/sites\/3896\/2019\/02\/08205946\/CNX_Precalc_Figure_01_06_011F.jpg\" alt=\"Graph an absolute function with x-intercepts at -2 and 1.5.\" width=\"731\" height=\"476\" \/><\/p>\n<p class=\"wp-caption-text\"><strong>Figure 9.<\/strong><\/p>\n<\/div>\n<\/div>\n<\/div>\n<\/div>\n<\/div>\n<\/div>\n<\/div>\n<div id=\"fs-id1165137599670\" class=\"precalculus tryit\">\n<h3>Try it #4<\/h3>\n<div id=\"ti_01_06_04\">\n<div id=\"fs-id1165135191411\">\n<p id=\"fs-id1165137843093\">For the function[latex]\\text{ }f\\left(x\\right)=|2x-1|-3,[\/latex]find the values of[latex]\\text{ }x\\text{ }[\/latex]such that[latex]\\text{ }f\\left(x\\right)=0.[\/latex]<\/p>\n<\/div>\n<div id=\"fs-id1165137939483\">\n<div class=\"qa-wrapper\" style=\"display: block\"><span class=\"show-answer collapsed\" style=\"cursor: pointer\" data-target=\"qfs-id1165137939483\">Show Solution<\/span><\/p>\n<div id=\"qfs-id1165137939483\" class=\"hidden-answer\" style=\"display: none\">\n<p id=\"fs-id1165137481390\">[latex]x=-1\\text{ }[\/latex]or[latex]\\text{ }\\text{ }x=2[\/latex]<\/p>\n<\/div>\n<\/div>\n<\/div>\n<\/div>\n<\/div>\n<div id=\"fs-id1165135175321\" class=\"precalculus qa key-takeaways\">\n<h3>Q&amp;A<\/h3>\n<p id=\"fs-id1165135606935\"><strong>Should we always expect two answers when solving[latex]\\text{ }|A|=B?[\/latex]<\/strong><\/p>\n<p id=\"fs-id1165137755892\"><em>No. We may find one, two, or even no answers. For example, there is no solution to<\/em>[latex]\\text{ }2+|3x-5|=1.[\/latex]<\/p>\n<\/div>\n<div id=\"fs-id1165137911662\" class=\"precalculus howto examples\">\n<h3>How To<\/h3>\n<p id=\"fs-id1165137647413\"><strong>Given an absolute value equation, solve it.<\/strong><\/p>\n<ol id=\"fs-id1165137589466\" type=\"1\">\n<li>Isolate the absolute value term.<\/li>\n<li>Use[latex]\\text{ }|A|=B\\text{ }[\/latex]to write[latex]\\text{ }A=B\\text{ }[\/latex]or[latex]\\text{ }A=\\mathrm{-B}.[\/latex]<\/li>\n<li>Solve for[latex]\\text{ }x.[\/latex]<\/li>\n<\/ol>\n<\/div>\n<div id=\"Example_01_06_05\" class=\"textbox examples\">\n<div id=\"fs-id1165137727865\">\n<div id=\"fs-id1165135195112\">\n<h3>example 5: Solving an Absolute Value Equation<\/h3>\n<p id=\"fs-id1165137695200\">Solve[latex]\\text{ }1=4|x-2|+2.[\/latex]<\/p>\n<\/div>\n<div id=\"fs-id1165137561245\">\n<div class=\"qa-wrapper\" style=\"display: block\"><span class=\"show-answer collapsed\" style=\"cursor: pointer\" data-target=\"qfs-id1165137561245\">Show Solution<\/span><\/p>\n<div id=\"qfs-id1165137561245\" class=\"hidden-answer\" style=\"display: none\">\n<p id=\"fs-id1165135210177\">Isolating the absolute value on one side of the equation gives the following.<\/p>\n<div id=\"fs-id1165137732202\" class=\"unnumbered\" style=\"text-align: center\">[latex]\\begin{array}{l}\\text{ }\\text{ }\\text{ }\\text{ }\\text{ }\\text{ }\\text{ }\\text{ }1=4|x-2|+2\\hfill \\\\ \\text{ }\\text{ }-1=4|x-2|\\hfill \\\\ \\text{ }-\\frac{1}{4}=|x-2|\\hfill \\end{array}[\/latex]<\/div>\n<p id=\"fs-id1165137611734\">The absolute value always returns a positive value, so it is impossible for the absolute value to equal a negative value. At this point, we notice that this equation has no solutions.<\/p>\n<\/div>\n<\/div>\n<\/div>\n<\/div>\n<\/div>\n<div id=\"fs-id1165137465993\" class=\"precalculus qa key-takeaways\">\n<h3>Q&amp;A<\/h3>\n<p id=\"fs-id1165137573052\"><strong>In <a class=\"autogenerated-content\" href=\"#Example_01_06_05\">(Example)<\/a>, if[latex]\\text{ }f\\left(x\\right)=1\\text{ }[\/latex]and[latex]\\text{ }g\\left(x\\right)=4|x-2|+2\\text{ }[\/latex]were graphed on the same set of axes, would the graphs intersect?<\/strong><\/p>\n<p id=\"fs-id1165137602208\"><em>No. The graphs of[latex]\\text{ }f\\text{ }[\/latex]and[latex]\\text{ }g\\text{ }[\/latex]would not intersect, as shown in <a class=\"autogenerated-content\" href=\"#Figure_01_06_012\">(Figure)<\/a>. This confirms, graphically, that the equation[latex]\\text{ }1=4|x-2|+2\\text{ }[\/latex]has no solution.<\/em><\/p>\n<\/div>\n<div id=\"Figure_01_06_012\" class=\"small\">\n<div style=\"width: 497px\" class=\"wp-caption aligncenter\"><img loading=\"lazy\" decoding=\"async\" src=\"https:\/\/s3-us-west-2.amazonaws.com\/courses-images\/wp-content\/uploads\/sites\/3896\/2019\/02\/08205949\/CNX_Precalc_Figure_01_06_012.jpg\" alt=\"Graph of g(x)=4|x-2|+2 and f(x)=1.\" width=\"487\" height=\"476\" \/><\/p>\n<p class=\"wp-caption-text\"><strong>Figure 10.<\/strong><\/p>\n<\/div>\n<\/div>\n<div class=\"precalculus tryit\">\n<h3>Try it #5<\/h3>\n<div id=\"ti_01_06_05\">\n<div id=\"fs-id1165137735929\">\n<p id=\"fs-id1165137735930\">Find where the graph of the function[latex]\\text{ }f\\left(x\\right)=-|x+2|+3\\text{ }[\/latex]intersects the horizontal and vertical axes.<\/p>\n<\/div>\n<div id=\"fs-id1165134057566\">\n<div class=\"qa-wrapper\" style=\"display: block\"><span class=\"show-answer collapsed\" style=\"cursor: pointer\" data-target=\"qfs-id1165134057566\">Show Solution<\/span><\/p>\n<div id=\"qfs-id1165134057566\" class=\"hidden-answer\" style=\"display: none\">\n<p id=\"fs-id1165137452134\">[latex]f\\left(0\\right)=1,\\text{ }[\/latex]so the graph intersects the vertical axis at[latex]\\text{ }\\left(0,1\\right).\\text{ }[\/latex][latex]\\text{ }f\\left(x\\right)=0\\text{ }[\/latex]when[latex]\\text{ }x=-5\\text{ }[\/latex]and[latex]\\text{ }x=1\\text{ }[\/latex]so the graph intersects the horizontal axis at[latex]\\text{ }\\left(-5,0\\right)\\text{ }[\/latex]and[latex]\\text{ }\\left(1,0\\right).[\/latex]<\/p>\n<\/div>\n<\/div>\n<\/div>\n<\/div>\n<\/div>\n<\/div>\n<div id=\"fs-id1165135571678\" class=\"bc-section section\">\n<h3>Solving an Absolute Value Inequality<\/h3>\n<p id=\"fs-id1165137583863\">Absolute value equations may not always involve equalities. Instead, we may need to solve an equation within a range of values. We would use an absolute value inequality to solve such an equation. An <strong>absolute value inequality<\/strong> is an equation of the form<\/p>\n<div id=\"fs-id1165134065110\" class=\"unnumbered\" style=\"text-align: center\">[latex]|A|<B,|A|\\le B,|A|>B,\\text{ }\\text{ }\\text{or} \\text{ }\\text{ }|A|\\ge B,[\/latex]<\/div>\n<p id=\"fs-id1165135154162\">where an expression[latex]\\text{ }A\\text{ }[\/latex](and possibly but not usually[latex]\\text{ }B[\/latex]) depends on a variable[latex]\\text{ }x.\\text{ }[\/latex]Solving the inequality means finding the set of all[latex]\\text{ }x\\text{ }[\/latex]that satisfy the inequality. Usually this set will be an interval or the union of two intervals.<\/p>\n<p id=\"fs-id1165137580992\">There are two basic approaches to solving absolute value inequalities: graphical and algebraic. The advantage of the graphical approach is we can read the solution by interpreting the graphs of two functions. The advantage of the algebraic approach is it yields solutions that may be difficult to read from the graph.<\/p>\n<p id=\"fs-id1165137557647\">For example, we know that all numbers within 200 units of 0 may be expressed as<\/p>\n<div id=\"fs-id1165137543814\" class=\"unnumbered\" style=\"text-align: center\">[latex]|x|<200\\text{ }\\text{or}\\text{ }-200<x<200\\text{ }[\/latex]<\/div>\n<p id=\"fs-id1165137610749\">Suppose we want to know all possible returns on an investment if we could earn some amount of money within $200 of $600. We can solve algebraically for the set of values[latex]\\text{ }x\\text{ }[\/latex] such that the distance between[latex]\\text{ }x\\text{ }[\/latex]and 600 is less than 200. We represent the distance between[latex]\\text{ }x\\text{ }[\/latex] and 600 as[latex]\\text{ }|x-600|.[\/latex]<\/p>\n<div id=\"fs-id1165137755666\" class=\"unnumbered\" style=\"text-align: center\">[latex]\\begin{array}{}\\\\ |x-600|<200\\text{ or }-200<x-600<200\\\\ \\text{ }-200+600<x-600+600<200+600\\\\ \\text{ }400<x<800\\end{array}[\/latex]<\/div>\n<p id=\"fs-id1165137804310\">This means our returns would be between $400 and $800.<\/p>\n<p id=\"fs-id1165137507358\">Sometimes an absolute value inequality problem will be presented to us in terms of a shifted and\/or stretched or compressed absolute value function, where we must determine for which values of the input the function\u2019s output will be negative or positive.<\/p>\n<div id=\"fs-id1165137667916\" class=\"precalculus howto examples\">\n<h3>How To<\/h3>\n<p id=\"fs-id1165137502428\"><strong>Given an absolute value inequality of the form[latex]\\text{ }|x-A|\\le B\\text{ }[\/latex]for real numbers[latex]\\text{ }a\\text{ }[\/latex]and[latex]\\text{ }b\\text{ }[\/latex]where[latex]\\text{ }b\\text{ }[\/latex]is positive, solve the absolute value inequality algebraically.<\/strong><\/p>\n<ol id=\"fs-id1165137563287\" type=\"1\">\n<li>Find boundary points by solving[latex]\\text{ }|x-A|=B.\\text{ }[\/latex]<\/li>\n<li>Test intervals created by the boundary points to determine where[latex]\\text{ }|x-A|\\le B.[\/latex]<\/li>\n<li>Write the interval or union of intervals satisfying the inequality in interval, inequality, or set-builder notation.<\/li>\n<\/ol>\n<\/div>\n<div id=\"Example_01_06_06\" class=\"textbox examples\">\n<div id=\"fs-id1165135704112\">\n<div id=\"fs-id1165137401703\">\n<h3>Example 6: Solving an Absolute Value Inequality<\/h3>\n<p id=\"fs-id1165135342955\">Solve[latex]\\text{ }|x\\text{ }-5|\\le 4.[\/latex]<\/p>\n<\/div>\n<div id=\"fs-id1165137550840\">\n<div class=\"qa-wrapper\" style=\"display: block\"><span class=\"show-answer collapsed\" style=\"cursor: pointer\" data-target=\"qfs-id1165137550840\">Show Solution<\/span><\/p>\n<div id=\"qfs-id1165137550840\" class=\"hidden-answer\" style=\"display: none\">\n<p id=\"fs-id1165137645044\">With both approaches, we will need to know first where the corresponding equality is true. In this case we first will find where[latex]\\text{ }|x-5|=4.\\text{ }[\/latex]We do this because the absolute value is a function with no breaks, so the only way the function values can switch from being less than 4 to being greater than 4 is by passing through where the values equal 4. Solve[latex]\\text{ }|x-5|=4.[\/latex]<\/p>\n<div id=\"fs-id1165135341386\" class=\"unnumbered\" style=\"text-align: center\">[latex]\\begin{array}{lll}\\begin{array}{c}x-5=4\\\\ \\text{ }\\text{ }\\text{ }\\text{ }\\text{ }\\text{ }\\text{ }x=9\\end{array}\\hfill & \\text{ }\\text{ }\\text{ }\\text{or}\\text{ }\\text{ }\\text{ }\\hfill & \\begin{array}{c}x-5=-4\\\\ \\text{ }\\text{ }\\text{ }\\text{ }x=1\\end{array}\\hfill \\end{array}\\text{ }[\/latex]<\/div>\n<p id=\"fs-id1165137665217\">After determining that the absolute value is equal to 4 at[latex]\\text{ }x=1\\text{ }[\/latex]and[latex]\\text{ }x=9,\\text{ }[\/latex]we know the graph can change only from being less than 4 to greater than 4 at these values. This divides the number line up into three intervals:<\/p>\n<div id=\"fs-id1165137423933\" class=\"unnumbered\" style=\"text-align: center\">[latex]x<1,\\text{ }1<x<9,\\text{ and }x>9.[\/latex]<\/div>\n<p id=\"fs-id1165137422669\">To determine when the function is less than 4, we could choose a value in each interval and see if the output is less than or greater than 4, as shown in <a class=\"autogenerated-content\" href=\"#Table_01_06_01\">(Table)<\/a>.<\/p>\n<table style=\"border-collapse: collapse;width: 100%\">\n<tbody>\n<tr>\n<td style=\"width: 25%;text-align: center\" colspan=\"4\"><strong>Table 1<\/strong><\/td>\n<\/tr>\n<tr>\n<td style=\"width: 25%\"><strong>Interval test<\/strong>[latex]\\text{ }x[\/latex]<\/td>\n<td style=\"width: 25%\">[latex]f\\left(x\\right)[\/latex]<\/td>\n<td style=\"width: 1.69205%\">[latex]<4\\text{ }[\/latex]or[latex]\\text{ }>4?[\/latex]<\/td>\n<td style=\"width: 48.308%\"><\/td>\n<\/tr>\n<tr>\n<td style=\"width: 25%\">[latex]x<1[\/latex]<\/td>\n<td style=\"width: 25%\">0<\/td>\n<td style=\"width: 1.69205%\">[latex]|0-5|=5[\/latex]<\/td>\n<td style=\"width: 48.308%\">Greater than<\/td>\n<\/tr>\n<tr>\n<td style=\"width: 25%\">[latex]1<x<9[\/latex]<\/td>\n<td style=\"width: 25%\">6<\/td>\n<td style=\"width: 1.69205%\">[latex]|6-5|=1[\/latex]<\/td>\n<td style=\"width: 48.308%\">Less than<\/td>\n<\/tr>\n<tr>\n<td style=\"width: 25%\">[latex]x>9[\/latex]<\/td>\n<td style=\"width: 25%\">11<\/td>\n<td style=\"width: 1.69205%\">[latex]|11-5|=6[\/latex]<\/td>\n<td style=\"width: 48.308%\">Greater than<\/td>\n<\/tr>\n<\/tbody>\n<\/table>\n<p id=\"fs-id1165137558949\">Because[latex]\\text{ }1\\le x\\le 9\\text{ }[\/latex]is the only interval in which the output at the test value is less than 4, we can conclude that the solution to[latex]\\text{ }|x-5|\\le 4\\text{ }[\/latex]is[latex]\\text{ }1\\le x\\le 9,\\text{ }[\/latex]or[latex]\\text{ }\\left[1,9\\right].[\/latex]<\/p>\n<p id=\"fs-id1165137424051\">To use a graph, we can sketch the function[latex]\\text{ }f\\left(x\\right)=|x-5|.\\text{ }[\/latex]To help us see where the outputs are 4, the line[latex]\\text{ }g\\left(x\\right)=4\\text{ }[\/latex]could also be sketched as in <a class=\"autogenerated-content\" href=\"#Figure_01_06_013\">(Figure)<\/a>.<\/p>\n<div id=\"Figure_01_06_013\" class=\"small\">\n<div style=\"width: 497px\" class=\"wp-caption aligncenter\"><img loading=\"lazy\" decoding=\"async\" src=\"https:\/\/s3-us-west-2.amazonaws.com\/courses-images\/wp-content\/uploads\/sites\/3896\/2019\/02\/08205952\/CNX_Precalc_Figure_01_06_013.jpg\" alt=\"Graph of an absolute function and a vertical line, demonstrating how to see what outputs are less than the vertical line.\" width=\"487\" height=\"288\" \/><\/p>\n<p class=\"wp-caption-text\"><strong>Figure 11.\u00a0<\/strong>Graph to find the points satisfying an absolute value inequality.<\/p>\n<\/div>\n<\/div>\n<p id=\"fs-id1165137874583\">We can see the following:<\/p>\n<ul id=\"fs-id1165134148370\">\n<li>The output values of the absolute value are equal to 4 at[latex]\\text{ }x=1\\text{ }[\/latex]and[latex]\\text{ }x=9.[\/latex]<\/li>\n<li>The graph of[latex]\\text{ }f\\text{ }[\/latex]is below the graph of[latex]\\text{ }g\\text{ }[\/latex]on[latex]\\text{ }1<x<9.\\text{ }[\/latex]This means the output values of[latex]\\text{ }f\\left(x\\right)\\text{ }[\/latex]are less than the output values of[latex]\\text{ }g\\left(x\\right).[\/latex]<\/li>\n<li>The absolute value is less than or equal to 4 between these two points, when[latex]\\text{ }1\\le x\\le 9.\\text{ }[\/latex]In interval notation, this would be the interval[latex]\\text{ }\\left[1,9\\right].[\/latex]\n<div id=\"Figure_01_06_013\" class=\"small\"><\/div>\n<\/div>\n<\/div>\n<\/li>\n<\/ul>\n<\/div>\n<div id=\"fs-id1165135381301\">\n<h3>Analysis<\/h3>\n<p id=\"fs-id1165135689465\">For absolute value inequalities,<\/p>\n<div id=\"fs-id1165135650752\" class=\"unnumbered\" style=\"text-align: center\">[latex]\\begin{array}{lll}|x-A|<C,\\hfill & \\hfill & |x-A|>C,\\hfill \\\\ \\text{ }\\text{ }\\text{ }\\text{ }-C<x-A<C,\\hfill & \\hfill & x-A<-C\\text{ or }x-A>C.\\hfill \\end{array}[\/latex]<\/div>\n<p id=\"fs-id1165135195336\">The[latex]\\text{ }<\\text{ }[\/latex]or[latex]\\text{ }>\\text{ }[\/latex]symbol may be replaced by[latex]\\text{ }\\le \\text{ or }\\ge .[\/latex]<\/p>\n<p id=\"fs-id1165135524557\">So, for this example, we could use this alternative approach.<\/p>\n<div id=\"fs-id1165134226778\" class=\"unnumbered\" style=\"text-align: center\">[latex]\\begin{array}{llll}|\\text{ }x-5|\\le 4\\hfill & \\hfill & \\hfill & \\hfill \\\\ \\text{ }\\text{ }\\text{ }\\text{ }\\text{ }\\text{ }\\text{ }-4\\le x-5\\le 4\\hfill & \\hfill & \\hfill & \\text{Rewrite by removing the absolute value bars}.\\hfill \\\\ -4+5\\le x-5+5\\le 4+5\\hfill & \\hfill & \\hfill & \\text{Isolate the }x.\\hfill \\\\ \\text{ }\\text{ }\\text{ }\\text{ }\\text{ }\\text{ }\\text{ }\\text{ }\\text{ }\\text{ }\\text{ }\\text{ }\\text{ }\\text{ }1\\le x\\le 9\\hfill & \\hfill & \\hfill & \\hfill \\end{array}[\/latex]<\/div>\n<\/div>\n<\/div>\n<\/div>\n<div id=\"fs-id1165137762260\" class=\"precalculus tryit\">\n<h3>Try it #6<\/h3>\n<div id=\"ti_01_06_06\">\n<div>\n<p id=\"fs-id1165137450875\">Solve[latex]\\text{ }|x+2|\\le 6.[\/latex]<\/p>\n<\/div>\n<div id=\"fs-id1165137447691\">\n<div class=\"qa-wrapper\" style=\"display: block\"><span class=\"show-answer collapsed\" style=\"cursor: pointer\" data-target=\"qfs-id1165137447691\">Show Solution<\/span><\/p>\n<div id=\"qfs-id1165137447691\" class=\"hidden-answer\" style=\"display: none\">\n<p id=\"fs-id1165137447692\">[latex]-8\\le x\\le 4[\/latex]<\/p>\n<\/div>\n<\/div>\n<\/div>\n<\/div>\n<\/div>\n<div id=\"fs-id1165137530158\" class=\"precalculus howto examples\">\n<h3>How To<\/h3>\n<p id=\"fs-id1165135445865\"><strong>Given an absolute value function, solve for the set of inputs where the output is positive (or negative). <\/strong><\/p>\n<ol id=\"fs-id1165137572514\" type=\"1\">\n<li>Set the function equal to zero, and solve for the boundary points of the solution set.<\/li>\n<li>Use test points or a graph to determine where the function\u2019s output is positive or negative.<\/li>\n<\/ol>\n<\/div>\n<div id=\"Example_01_06_07\" class=\"textbox examples\">\n<div id=\"fs-id1165137409791\">\n<div id=\"fs-id1165137838822\">\n<h3>Example 7: Using a Graphical Approach to Solve Absolute Value Inequalities<\/h3>\n<p id=\"fs-id1165137933778\">Given the function [latex]f\\left(x\\right)=-\\frac{1}{2}|4x-5|+3,\\text{ }[\/latex] determine the [latex]x\\text{-}[\/latex]values for which the function values are negative.<\/p>\n<\/div>\n<div id=\"fs-id1165137921789\">\n<div class=\"qa-wrapper\" style=\"display: block\"><span class=\"show-answer collapsed\" style=\"cursor: pointer\" data-target=\"qfs-id1165137921789\">Show Solution<\/span><\/p>\n<div id=\"qfs-id1165137921789\" class=\"hidden-answer\" style=\"display: none\">\n<p id=\"fs-id1165137431799\">We are trying to determine where[latex]\\text{ }f\\left(x\\right)<0,\\text{ }[\/latex]which is when[latex]-\\frac{1}{2}\\text{ }|4x-5|+3<0.[\/latex]We begin by isolating the absolute value.<\/p>\n<div class=\"unnumbered\" style=\"text-align: center\">[latex]\\begin{array}{ll}-\\frac{1}{2}|4x-5|<-3\\begin{array}{cccc}& & & \\end{array}\\hfill & \\text{Multiply both sides by \u20132, and reverse the inequality}.\\hfill \\\\ \\text{ }\\text{ }\\text{ }\\text{ }\\text{ }\\text{ }\\text{ }\\text{ }\\text{ }\\text{ }|4x-5|>6\\hfill & \\hfill \\end{array}[\/latex]<\/div>\n<p id=\"fs-id1165135317447\">Next we solve for the equality[latex]\\text{ }|4x-5|=6.[\/latex]<\/p>\n<div id=\"fs-id1165135307916\" class=\"unnumbered\" style=\"text-align: center\">[latex]\\begin{array}{ll}4x-5=6\\text{}\\text{ or}\\hfill \\hfill & 4x-5=-6\\hfill \\\\ 4x-5=6\\hfill & \\text{ }\\text{ }\\text{ }\\text{ }\\text{ }\\text{ }\\text{ }\\text{ }\\text{ }\\text{ }4x=-1\\hfill \\\\ x=\\frac{11}{4}\\hfill & \\text{ }\\text{ }\\text{ }\\text{ }\\text{ }\\text{ }\\text{ }\\text{ }\\text{ }\\text{ }\\text{ }\\text{ }\\text{ }x=-\\frac{1}{4}\\hfill \\end{array}[\/latex]<\/div>\n<p id=\"fs-id1165135344887\">Now, we can examine the graph of[latex]\\text{ }f\\text{ }[\/latex]to observe where the output is negative. We will observe where the branches are below the <em>x<\/em>-axis. Notice that it is not even important exactly what the graph looks like, as long as we know that it crosses the horizontal axis at[latex]\\text{ }x=-\\frac{1}{4}\\text{ }[\/latex]and[latex]\\text{ }x=\\frac{11}{4}\\text{ }[\/latex]and that the graph has been reflected vertically. See <a class=\"autogenerated-content\" href=\"#Figure_01_06_014\">(Figure)<\/a><strong>.<\/strong><\/p>\n<div id=\"Figure_01_06_014\" class=\"small\">\n<div style=\"width: 497px\" class=\"wp-caption aligncenter\"><img loading=\"lazy\" decoding=\"async\" src=\"https:\/\/s3-us-west-2.amazonaws.com\/courses-images\/wp-content\/uploads\/sites\/3896\/2019\/02\/08205955\/CNX_Precalc_Figure_01_06_014.jpg\" alt=\"Graph of an absolute function with x-intercepts at -0.25 and 2.75.\" width=\"487\" height=\"365\" \/><\/p>\n<p class=\"wp-caption-text\"><strong>Figure 12.<\/strong><\/p>\n<\/div>\n<\/div>\n<p id=\"fs-id1165137725461\">We observe that the graph of the function is below the <em>x<\/em>-axis left of[latex]\\text{ }x=-\\frac{1}{4}\\text{ }[\/latex]and right of[latex]\\text{ }x=\\frac{11}{4}.\\text{ }[\/latex]This means the function values are negative to the left of the first horizontal intercept at[latex]\\text{ }x=-\\frac{1}{4},\\text{ }[\/latex]and negative to the right of the second intercept at[latex]\\text{ }x=\\frac{11}{4}.\\text{ }[\/latex]This gives us the solution to the inequality.<\/p>\n<div id=\"fs-id1165137460499\" class=\"unnumbered\" style=\"text-align: center\">[latex]x<-\\frac{1}{4}\\text{\u2003}\\text{or}\\text{\u2003}x>\\frac{11}{4}[\/latex]<\/div>\n<p id=\"fs-id1165135502945\">In interval notation, this would be[latex]\\text{ }\\left(-\\infty ,-0.25\\right)\\cup \\left(2.75,\\infty \\right).[\/latex]<\/p>\n<\/div>\n<\/div>\n<\/div>\n<\/div>\n<\/div>\n<div id=\"fs-id1165137805480\" class=\"precalculus tryit\">\n<h3>Try it #7<\/h3>\n<div id=\"ti_01_06_07\">\n<div id=\"fs-id1165137784437\">\n<p id=\"fs-id1165137784438\">Solve[latex]\\text{ }-2|k-4|\\le -6.[\/latex]<\/p>\n<\/div>\n<div id=\"fs-id1165135547314\">\n<div class=\"qa-wrapper\" style=\"display: block\"><span class=\"show-answer collapsed\" style=\"cursor: pointer\" data-target=\"qfs-id1165135547314\">Show Solution<\/span><\/p>\n<div id=\"qfs-id1165135547314\" class=\"hidden-answer\" style=\"display: none\">\n<p id=\"fs-id1165137767092\">[latex]k\\le 1\\text{ }[\/latex]or[latex]\\text{ }k\\ge 7;\\text{ }[\/latex]in interval notation, this would be[latex]\\text{ }\\left(-\\infty ,1\\right]\\cup \\left[7,\\infty \\right)[\/latex]<\/p>\n<\/div>\n<\/div>\n<\/div>\n<\/div>\n<\/div>\n<div id=\"fs-id1165134257615\" class=\"precalculus media\">\n<div class=\"textbox shaded\">\n<h3>Media:<\/h3>\n<p id=\"fs-id1165134332731\">Access these online resources for additional instruction and practice with absolute value.<\/p>\n<ul id=\"fs-id1165137508064\">\n<li><a href=\"http:\/\/openstax.org\/l\/graphabsvalue\">Graphing Absolute Value Functions<\/a><\/li>\n<li><a href=\"http:\/\/openstax.org\/l\/graphabsvalue2\">Graphing Absolute Value Functions 2<\/a><\/li>\n<li><a href=\"http:\/\/openstax.org\/l\/findeqabsval\">Equations of Absolute Value Function<\/a><\/li>\n<li><a href=\"http:\/\/openstax.org\/l\/findeqabsval2\">Equations of Absolute Value Function 2<\/a><\/li>\n<li><a href=\"http:\/\/openstax.org\/l\/solveabsvalueeq\">Solving Absolute Value Equations<\/a><\/li>\n<\/ul>\n<\/div>\n<\/div>\n<\/div>\n<div id=\"fs-id1165133291312\" class=\"textbox key-takeaways\">\n<h3>Key Concepts<\/h3>\n<ul id=\"fs-id1165135332513\">\n<li>The absolute value function is commonly used to measure distances between points. See <a class=\"autogenerated-content\" href=\"#Example_01_06_01\">(Figure)<\/a>.<\/li>\n<li>Applied problems, such as ranges of possible values, can also be solved using the absolute value function. See <a class=\"autogenerated-content\" href=\"#Example_01_06_02\">(Figure)<\/a>.<\/li>\n<li>The graph of the absolute value function resembles a letter V. It has a corner point at which the graph changes direction. See <a class=\"autogenerated-content\" href=\"#Example_01_06_03\">(Figure)<\/a>.<\/li>\n<li>In an absolute value equation, an unknown variable is the input of an absolute value function.<\/li>\n<li>If the absolute value of an expression is set equal to a positive number, expect two solutions for the unknown variable. See <a class=\"autogenerated-content\" href=\"#Example_01_06_04\">(Figure)<\/a>.<\/li>\n<li>An absolute value equation may have one solution, two solutions, or no solutions. See <a class=\"autogenerated-content\" href=\"#Example_01_06_05\">(Figure)<\/a>.<\/li>\n<li>An absolute value inequality is similar to an absolute value equation but takes the form [latex]\\text{ }|A|<B,\\text{ }\\text{ }\\text{ }|A|\\le B,\\text{ }\\text{ }\\text{ }\\text{ }|A|>B,\\text{ }\\text{ }\\text{or }\\text{ }\\text{ }|A|\\ge B.[\/latex]It can be solved by determining the boundaries of the solution set and then testing which segments are in the set. See <a class=\"autogenerated-content\" href=\"#Example_01_06_06\">(Figure)<\/a>.<\/li>\n<li>Absolute value inequalities can also be solved graphically. See <a class=\"autogenerated-content\" href=\"#Example_01_06_07\">(Figure)<\/a>.<\/li>\n<\/ul>\n<\/div>\n<div class=\"textbox exercises\">\n<h3>Section Exercise<\/h3>\n<div id=\"fs-id1165137406985\" class=\"bc-section section\">\n<h4>Verbal<\/h4>\n<div id=\"fs-id1165137734873\">\n<div id=\"fs-id1165135510060\">\n<p id=\"fs-id1165134347447\">1. How do you solve an absolute value equation?<\/p>\n<\/div>\n<div id=\"fs-id1165135206149\">\n<div class=\"qa-wrapper\" style=\"display: block\"><span class=\"show-answer collapsed\" style=\"cursor: pointer\" data-target=\"qfs-id1165135206149\">Show Solution<\/span><\/p>\n<div id=\"qfs-id1165135206149\" class=\"hidden-answer\" style=\"display: none\">\n<p id=\"fs-id1165135189754\">Isolate the absolute value term so that the equation is of the form[latex]\\text{ }|A|=B.\\text{ }[\/latex]Form one equation by setting the expression inside the absolute value symbol,[latex]\\text{ }A,\\text{ }[\/latex]equal to the expression on the other side of the equation,[latex]\\text{ }B.\\text{ }[\/latex]Form a second equation by setting[latex]\\text{ }A\\text{ }[\/latex]equal to the opposite of the expression on the other side of the equation,[latex]\\text{ }-B.\\text{ }[\/latex]Solve each equation for the variable.<\/p>\n<\/div>\n<\/div>\n<\/div>\n<\/div>\n<div id=\"fs-id1165137593210\">\n<div id=\"fs-id1165131968049\">\n<p id=\"fs-id1165135440055\">2. How can you tell whether an absolute value function has two <em>x<\/em>-intercepts without graphing the function?<\/p>\n<\/div>\n<\/div>\n<div id=\"fs-id1165133103957\">\n<div id=\"fs-id1165133103959\">\n<p>3. When solving an absolute value function, the isolated absolute value term is equal to a negative number. What does that tell you about the graph of the absolute value function?<\/p>\n<\/div>\n<div id=\"fs-id1165134475281\">\n<div class=\"qa-wrapper\" style=\"display: block\"><span class=\"show-answer collapsed\" style=\"cursor: pointer\" data-target=\"qfs-id1165134475281\">Show Solution<\/span><\/p>\n<div id=\"qfs-id1165134475281\" class=\"hidden-answer\" style=\"display: none\">\n<p id=\"fs-id1165137662762\">The graph of the absolute value function does not cross the[latex]\\text{ }x[\/latex]-axis, so the graph is either completely above or completely below the[latex]\\text{ }x[\/latex]-axis.<\/p>\n<\/div>\n<\/div>\n<\/div>\n<\/div>\n<div id=\"fs-id1165135264708\">\n<div id=\"fs-id1165135149122\">\n<p id=\"fs-id1165135149124\">4. How can you use the graph of an absolute value function to determine the <em>x<\/em>-values for which the function values are negative?<\/p>\n<\/div>\n<\/div>\n<div id=\"fs-id1165137645236\">\n<div id=\"fs-id1165135414273\">\n<p id=\"fs-id1165137475324\">5. How do you solve an absolute value inequality algebraically?<\/p>\n<\/div>\n<div id=\"fs-id1165135533156\">\n<div class=\"qa-wrapper\" style=\"display: block\"><span class=\"show-answer collapsed\" style=\"cursor: pointer\" data-target=\"qfs-id1165135533156\">Show Solution<\/span><\/p>\n<div id=\"qfs-id1165135533156\" class=\"hidden-answer\" style=\"display: none\">\n<p id=\"fs-id1165135533157\">First determine the boundary points by finding the solution(s) of the equation. Use the boundary points to form possible solution intervals. Choose a test value in each interval to determine which values satisfy the inequality.<\/p>\n<\/div>\n<\/div>\n<\/div>\n<\/div>\n<\/div>\n<div id=\"fs-id1165134273549\" class=\"bc-section section\">\n<h4>Algebraic<\/h4>\n<div id=\"fs-id1165137841613\">\n<div id=\"fs-id1165137841615\">\n<p id=\"fs-id1165137579699\">6. Describe all numbers[latex]\\text{ }x\\text{ }[\/latex]that are at a distance of 4 from the number 8. Express this using absolute value notation.<\/p>\n<\/div>\n<\/div>\n<div id=\"fs-id1165135445894\">\n<div>\n<p id=\"fs-id1165135169187\">7. Describe all numbers[latex]\\text{ }x\\text{ }[\/latex]that are at a distance of[latex]\\text{ }\\frac{1}{2}\\text{ }[\/latex]from the number \u22124. Express this using absolute value notation.<\/p>\n<\/div>\n<div id=\"fs-id1165135356596\">\n<div class=\"qa-wrapper\" style=\"display: block\"><span class=\"show-answer collapsed\" style=\"cursor: pointer\" data-target=\"qfs-id1165135356596\">Show Solution<\/span><\/p>\n<div id=\"qfs-id1165135356596\" class=\"hidden-answer\" style=\"display: none\">\n<p id=\"fs-id1165134278683\">[latex]\\text{ }|x+4|=\\frac{1}{2}\\text{ }[\/latex]<\/p>\n<\/div>\n<\/div>\n<\/div>\n<\/div>\n<div id=\"fs-id1165137542576\">\n<div id=\"fs-id1165137648320\">\n<p id=\"fs-id1165137648322\">8. Describe the situation in which the distance that point[latex]\\text{ }x\\text{ }[\/latex]is from 10 is at least 15 units. Express this using absolute value notation.<\/p>\n<\/div>\n<\/div>\n<div id=\"fs-id1165134057540\">\n<div id=\"fs-id1165137464076\">\n<p id=\"fs-id1165137464078\">9. Find all function values[latex]\\text{ }f\\left(x\\right)\\text{ }[\/latex]such that the distance from[latex]\\text{ }f\\left(x\\right)\\text{ }[\/latex]to the value 8 is less than 0.03 units. Express this using absolute value notation.<\/p>\n<\/div>\n<div id=\"fs-id1165137541376\">\n<div class=\"qa-wrapper\" style=\"display: block\"><span class=\"show-answer collapsed\" style=\"cursor: pointer\" data-target=\"qfs-id1165137541376\">Show Solution<\/span><\/p>\n<div id=\"qfs-id1165137541376\" class=\"hidden-answer\" style=\"display: none\">\n<p id=\"fs-id1165137572565\">[latex]|f\\left(x\\right)-8|<0.03[\/latex]<\/p>\n<\/div>\n<\/div>\n<\/div>\n<\/div>\n<p id=\"fs-id1165137658780\">For the following exercises, solve the equations below and express the answer using set notation.<\/p>\n<div id=\"fs-id1165137547457\">\n<div id=\"fs-id1165135176655\">\n<p id=\"fs-id1165137823605\">10. [latex]|x+3|=9[\/latex]<\/p>\n<\/div>\n<\/div>\n<div id=\"fs-id1165135254647\">\n<div id=\"fs-id1165135254649\">\n<p id=\"fs-id1165135253828\">11. [latex]|6-x|=5[\/latex]<\/p>\n<\/div>\n<div id=\"fs-id1165137424495\">\n<div class=\"qa-wrapper\" style=\"display: block\"><span class=\"show-answer collapsed\" style=\"cursor: pointer\" data-target=\"qfs-id1165137424495\">Show Solution<\/span><\/p>\n<div id=\"qfs-id1165137424495\" class=\"hidden-answer\" style=\"display: none\">\n<p id=\"fs-id1165137424497\">[latex]\\left\\{1,11\\right\\}[\/latex]<\/p>\n<\/div>\n<\/div>\n<\/div>\n<\/div>\n<div id=\"fs-id1165137930354\">\n<div id=\"fs-id1165137930356\">\n<p id=\"fs-id1165137639146\">12. [latex]|5x-2|=11[\/latex]<\/p>\n<\/div>\n<\/div>\n<div id=\"fs-id1165137594492\">\n<div id=\"fs-id1165137594494\">\n<p id=\"fs-id1165137436276\">13. [latex]|4x-2|=11[\/latex]<\/p>\n<\/div>\n<div id=\"fs-id1165137600494\">\n<div class=\"qa-wrapper\" style=\"display: block\"><span class=\"show-answer collapsed\" style=\"cursor: pointer\" data-target=\"qfs-id1165137600494\">Show Solution<\/span><\/p>\n<div id=\"qfs-id1165137600494\" class=\"hidden-answer\" style=\"display: none\">[latex]\\left\\{\\frac{9}{4},\\text{ }\\text{ }\\text{ }\\text{ }\\text{ }\\frac{13}{4}\\right\\}[\/latex]<\/div>\n<\/div>\n<\/div>\n<\/div>\n<div id=\"fs-id1165135440214\">\n<div id=\"fs-id1165137833911\">\n<p id=\"fs-id1165137833914\">14. [latex]2|4-x|=7[\/latex]<\/p>\n<\/div>\n<\/div>\n<div id=\"fs-id1165135641672\">\n<div id=\"fs-id1165135641675\">\n<p id=\"fs-id1165137410330\">15. [latex]3|5-x|=5[\/latex]<\/p>\n<\/div>\n<div id=\"fs-id1165137411215\">\n<div class=\"qa-wrapper\" style=\"display: block\"><span class=\"show-answer collapsed\" style=\"cursor: pointer\" data-target=\"qfs-id1165137411215\">Show Solution<\/span><\/p>\n<div id=\"qfs-id1165137411215\" class=\"hidden-answer\" style=\"display: none\">\n<p id=\"fs-id1165137411217\">[latex]\\left\\{\\frac{10}{3},\\text{ }\\text{ }\\text{ }\\text{ }\\text{ }\\frac{20}{3}\\right\\}[\/latex]<\/p>\n<\/div>\n<\/div>\n<\/div>\n<\/div>\n<div id=\"fs-id1165135241396\">\n<div id=\"fs-id1165135192397\">\n<p id=\"fs-id1165135192399\">16. [latex]3|x+1|-4=5[\/latex]<\/p>\n<\/div>\n<\/div>\n<div id=\"fs-id1165137451880\">\n<div id=\"fs-id1165137451883\">\n<p id=\"fs-id1165137439227\">17. [latex]5|x-4|-7=2[\/latex]<\/p>\n<\/div>\n<div>\n<p id=\"fs-id1165134108517\">\n<div class=\"qa-wrapper\" style=\"display: block\"><span class=\"show-answer collapsed\" style=\"cursor: pointer\" data-target=\"q612972\">Show Solution<\/span><\/p>\n<div id=\"q612972\" class=\"hidden-answer\" style=\"display: none\">\n<p>[latex]\\left\\{\\frac{11}{5},\\text{ }\\text{ }\\text{ }\\text{ }\\text{ }\\frac{29}{5}\\right\\}[\/latex]<\/p><\/div>\n<\/div>\n<\/div>\n<\/div>\n<div id=\"fs-id1165137803650\">\n<div id=\"fs-id1165137803652\">\n<p id=\"fs-id1165135613399\">18. [latex]0=-|x-3|+2[\/latex]<\/p>\n<\/div>\n<\/div>\n<div id=\"fs-id1165137442574\">\n<div id=\"fs-id1165137442576\">\n<p>19. [latex]2|x-3|+1=2[\/latex]<\/p>\n<\/div>\n<div id=\"fs-id1165135151997\">\n<div class=\"qa-wrapper\" style=\"display: block\"><span class=\"show-answer collapsed\" style=\"cursor: pointer\" data-target=\"qfs-id1165135151997\">Show Solution<\/span><\/p>\n<div id=\"qfs-id1165135151997\" class=\"hidden-answer\" style=\"display: none\">\n<p id=\"fs-id1165137585705\">[latex]\\left\\{\\frac{5}{2},\\frac{7}{2}\\right\\}[\/latex]<\/p>\n<\/div>\n<\/div>\n<\/div>\n<\/div>\n<div id=\"fs-id1165137761108\">\n<div id=\"fs-id1165131911969\">\n<p id=\"fs-id1165131911971\">20. [latex]|3x-2|=7[\/latex]<\/p>\n<\/div>\n<\/div>\n<div id=\"fs-id1165137838065\">\n<div id=\"fs-id1165137571104\">\n<p id=\"fs-id1165137571106\">21. [latex]|3x-2|=-7[\/latex]<\/p>\n<\/div>\n<div id=\"fs-id1165137809984\">\n<div class=\"qa-wrapper\" style=\"display: block\"><span class=\"show-answer collapsed\" style=\"cursor: pointer\" data-target=\"qfs-id1165137809984\">Show Solution<\/span><\/p>\n<div id=\"qfs-id1165137809984\" class=\"hidden-answer\" style=\"display: none\">\n<p id=\"fs-id1165135182933\">No solution<\/p>\n<\/div>\n<\/div>\n<\/div>\n<\/div>\n<div id=\"fs-id1165137793832\">\n<div id=\"fs-id1165134393100\">\n<p id=\"fs-id1165134393102\">22. [latex]|\\frac{1}{2}x-5|=11[\/latex]<\/p>\n<\/div>\n<\/div>\n<div id=\"fs-id1165137401505\">\n<div id=\"fs-id1165137401507\">\n<p id=\"fs-id1165137852038\">23. [latex]|\\frac{1}{3}x+5|=14[\/latex]<\/p>\n<\/div>\n<div id=\"fs-id1165137854997\">\n<div class=\"qa-wrapper\" style=\"display: block\"><span class=\"show-answer collapsed\" style=\"cursor: pointer\" data-target=\"qfs-id1165137854997\">Show Solution<\/span><\/p>\n<div id=\"qfs-id1165137854997\" class=\"hidden-answer\" style=\"display: none\">\n<p id=\"fs-id1165137564109\">[latex]\\left\\{-57,27\\right\\}[\/latex]<\/p>\n<\/div>\n<\/div>\n<\/div>\n<\/div>\n<div id=\"fs-id1165135160638\">\n<div id=\"fs-id1165137769919\">\n<p id=\"fs-id1165137769921\">24. [latex]-|\\frac{1}{3}x+5|+14=0[\/latex]<\/p>\n<\/div>\n<\/div>\n<p id=\"fs-id1165137589731\">For the following exercises, find the <em>x<\/em>&#8211; and <em>y<\/em>-intercepts of the graphs of each function.<\/p>\n<div id=\"fs-id1165135190614\">\n<div id=\"fs-id1165134117307\">\n<p id=\"fs-id1165134117309\">25. [latex]f\\left(x\\right)=2|x+1|-10[\/latex]<\/p>\n<\/div>\n<div id=\"fs-id1165134557389\">\n<div class=\"qa-wrapper\" style=\"display: block\"><span class=\"show-answer collapsed\" style=\"cursor: pointer\" data-target=\"qfs-id1165134557389\">Show Solution<\/span><\/p>\n<div id=\"qfs-id1165134557389\" class=\"hidden-answer\" style=\"display: none\">\n<p id=\"fs-id1165134557391\">[latex]\\left(0,-8\\right);\\text{ }\\left(-6,0\\right),\\text{ }\\left(4,0\\right)[\/latex]<\/p>\n<\/div>\n<\/div>\n<\/div>\n<\/div>\n<div id=\"fs-id1165134401702\">\n<div id=\"fs-id1165135362510\">\n<p id=\"fs-id1165135362512\">26. [latex]f\\left(x\\right)=4|x-3|+4[\/latex]<\/p>\n<\/div>\n<\/div>\n<div id=\"fs-id1165137824535\">\n<div id=\"fs-id1165137824537\">\n<p id=\"fs-id1165134220856\">27. [latex]f\\left(x\\right)=-3|x-2|-1[\/latex]<\/p>\n<\/div>\n<div>\n<p id=\"fs-id1165137433352\">\n<div class=\"qa-wrapper\" style=\"display: block\"><span class=\"show-answer collapsed\" style=\"cursor: pointer\" data-target=\"q453586\">Show Solution<\/span><\/p>\n<div id=\"q453586\" class=\"hidden-answer\" style=\"display: none\">\n<p>[latex]\\left(0,-7\\right);\\text{ }[\/latex]no[latex]\\text{ }x[\/latex]-intercepts<\/p><\/div>\n<\/div>\n<\/div>\n<\/div>\n<div id=\"fs-id1165134371172\">\n<div id=\"fs-id1165134371174\">\n<p id=\"fs-id1165137590699\">28. [latex]f\\left(x\\right)=-2|x+1|+6[\/latex]<\/p>\n<\/div>\n<\/div>\n<p id=\"fs-id1165134117280\">For the following exercises, solve each inequality and write the solution in interval notation.<\/p>\n<div id=\"fs-id1165137656160\">\n<div id=\"fs-id1165137656163\">\n<p id=\"fs-id1165137938872\">29. [latex]|x-2|>10[\/latex]<\/p>\n<\/div>\n<div id=\"fs-id1165137427184\">\n<div class=\"qa-wrapper\" style=\"display: block\"><span class=\"show-answer collapsed\" style=\"cursor: pointer\" data-target=\"qfs-id1165137427184\">Show Solution<\/span><\/p>\n<div id=\"qfs-id1165137427184\" class=\"hidden-answer\" style=\"display: none\">\n<p id=\"fs-id1165137427186\">[latex]\\left(-\\infty ,-8\\right)\\cup \\left(12,\\infty \\right)[\/latex]<\/p>\n<\/div>\n<\/div>\n<\/div>\n<\/div>\n<div id=\"fs-id1165137407052\">\n<div id=\"fs-id1165135508305\">\n<p id=\"fs-id1165135508307\">30. [latex]2|v-7|-4\\ge 42[\/latex]<\/p>\n<\/div>\n<\/div>\n<div id=\"fs-id1165135187122\">\n<div id=\"fs-id1165135187125\">\n<p id=\"fs-id1165137418895\">31. [latex]|3x-4|\\le 8[\/latex]<\/p>\n<\/div>\n<div id=\"fs-id1165137445354\">\n<div class=\"qa-wrapper\" style=\"display: block\"><span class=\"show-answer collapsed\" style=\"cursor: pointer\" data-target=\"qfs-id1165137445354\">Show Solution<\/span><\/p>\n<div id=\"qfs-id1165137445354\" class=\"hidden-answer\" style=\"display: none\">\n<p id=\"fs-id1165137715044\">[latex]\\frac{-4}{3}\\le x\\le 4[\/latex]<\/p>\n<\/div>\n<\/div>\n<\/div>\n<\/div>\n<div id=\"fs-id1165135320061\">\n<div>\n<p id=\"fs-id1165135195164\">32. [latex]|x-4|\\ge 8[\/latex]<\/p>\n<\/div>\n<\/div>\n<div id=\"fs-id1165135196794\">\n<div id=\"fs-id1165135196796\">\n<p id=\"fs-id1165135641739\">33. [latex]|3x-5|\\ge 13[\/latex]<\/p>\n<\/div>\n<div id=\"fs-id1165137812206\">\n<div class=\"qa-wrapper\" style=\"display: block\"><span class=\"show-answer collapsed\" style=\"cursor: pointer\" data-target=\"qfs-id1165137812206\">Show Solution<\/span><\/p>\n<div id=\"qfs-id1165137812206\" class=\"hidden-answer\" style=\"display: none\">[latex]\\left(-\\infty ,-\\frac{8}{3}\\right]\\cup \\left[6,\\infty \\right)[\/latex]<\/div>\n<\/div>\n<\/div>\n<\/div>\n<div>\n<div id=\"fs-id1165137448163\">\n<p id=\"fs-id1165137448165\">34. [latex]|3x-5|\\ge -13[\/latex]<\/p>\n<\/div>\n<\/div>\n<div id=\"fs-id1165135149793\">\n<div id=\"fs-id1165137784178\">\n<p id=\"fs-id1165137784180\">35. [latex]|\\frac{3}{4}x-5|\\ge 7[\/latex]<\/p>\n<\/div>\n<div id=\"fs-id1165135377121\">\n<div class=\"qa-wrapper\" style=\"display: block\"><span class=\"show-answer collapsed\" style=\"cursor: pointer\" data-target=\"qfs-id1165135377121\">Show Solution<\/span><\/p>\n<div id=\"qfs-id1165135377121\" class=\"hidden-answer\" style=\"display: none\">\n<p id=\"fs-id1165135377124\">[latex]\\left(-\\infty ,-\\frac{8}{3}\\right]\\cup \\left[16,\\infty \\right)[\/latex]<\/p>\n<\/div>\n<\/div>\n<\/div>\n<\/div>\n<div id=\"fs-id1165137419461\">\n<div id=\"fs-id1165137410039\">\n<p id=\"fs-id1165137410042\">36. [latex]|\\frac{3}{4}x-5|+1\\le 16[\/latex]<\/p>\n<\/div>\n<\/div>\n<\/div>\n<div class=\"bc-section section\">\n<h4>Graphical<\/h4>\n<p id=\"fs-id1165133047532\">For the following exercises, graph the absolute value function. Plot at least five points by hand for each graph.<\/p>\n<div id=\"fs-id1165137891404\">\n<div id=\"fs-id1165137817696\">\n<p id=\"fs-id1165137817699\">37. [latex]y=|x-1|[\/latex]<\/p>\n<\/div>\n<div><span id=\"fs-id1165135499906\"><\/p>\n<div class=\"qa-wrapper\" style=\"display: block\"><span class=\"show-answer collapsed\" style=\"cursor: pointer\" data-target=\"q601067\">Show Solution<\/span><\/p>\n<div id=\"q601067\" class=\"hidden-answer\" style=\"display: none\"><img decoding=\"async\" class=\"aligncenter\" src=\"https:\/\/s3-us-west-2.amazonaws.com\/courses-images\/wp-content\/uploads\/sites\/3896\/2019\/02\/08205957\/CNX_Precalc_Figure_01_06_201.jpg\" alt=\"Graph of an absolute function with points at (-1, 2), (0, 1), (1, 0), (2, 1), and (3, 2).\" \/><\/div>\n<\/div>\n<p><\/span><\/div>\n<\/div>\n<div id=\"fs-id1165137679099\">\n<div id=\"fs-id1165137679101\">\n<p id=\"fs-id1165137418760\">38. [latex]y=|x+1|[\/latex]<\/p>\n<\/div>\n<\/div>\n<div id=\"fs-id1165135422938\">\n<div id=\"fs-id1165135422940\">\n<p id=\"fs-id1165137652979\">39. [latex]y=|x|+1[\/latex]<\/p>\n<\/div>\n<div id=\"fs-id1165137414774\">\n<div class=\"qa-wrapper\" style=\"display: block\"><span class=\"show-answer collapsed\" style=\"cursor: pointer\" data-target=\"qfs-id1165137414774\">Show Solution<\/span><\/p>\n<div id=\"qfs-id1165137414774\" class=\"hidden-answer\" style=\"display: none\"><span id=\"fs-id1165137658298\"><img decoding=\"async\" class=\"aligncenter\" src=\"https:\/\/s3-us-west-2.amazonaws.com\/courses-images\/wp-content\/uploads\/sites\/3896\/2019\/02\/08205959\/CNX_Precalc_Figure_01_06_203.jpg\" alt=\"Graph of an absolute function with points at (-2, 3), (-1, 2), (0, 1), (1, 2), and (2, 3).\" \/><\/span><\/div>\n<\/div>\n<\/div>\n<\/div>\n<p id=\"fs-id1165137406944\">For the following exercises, graph the given functions by hand.<\/p>\n<div id=\"fs-id1165135332726\">\n<div id=\"fs-id1165135332729\">\n<p id=\"fs-id1165135251459\">40. [latex]y=|x|-2[\/latex]<\/p>\n<\/div>\n<\/div>\n<div id=\"fs-id1165137601710\">\n<div id=\"fs-id1165137601713\">\n<p id=\"fs-id1165137419974\">41. [latex]y=-|x|[\/latex]<\/p>\n<\/div>\n<div id=\"fs-id1165137400044\">\n<div class=\"qa-wrapper\" style=\"display: block\"><span class=\"show-answer collapsed\" style=\"cursor: pointer\" data-target=\"qfs-id1165137400044\">Show Solution<\/span><\/p>\n<div id=\"qfs-id1165137400044\" class=\"hidden-answer\" style=\"display: none\"><span id=\"fs-id1165135160170\"><img decoding=\"async\" class=\"aligncenter\" src=\"https:\/\/s3-us-west-2.amazonaws.com\/courses-images\/wp-content\/uploads\/sites\/3896\/2019\/02\/08210002\/CNX_Precalc_Figure_01_06_205.jpg\" alt=\"Graph of an absolute function.\" \/><\/span><\/div>\n<\/div>\n<\/div>\n<\/div>\n<div id=\"fs-id1165137735265\">\n<div id=\"fs-id1165137431347\">\n<p id=\"fs-id1165137431349\">42. [latex]y=-|x|-2[\/latex]<\/p>\n<\/div>\n<\/div>\n<div id=\"fs-id1165137731590\">\n<div id=\"fs-id1165137603675\">\n<p id=\"fs-id1165137603678\">43. [latex]y=-|x-3|-2[\/latex]<\/p>\n<\/div>\n<div id=\"fs-id1165137645253\">\n<div class=\"qa-wrapper\" style=\"display: block\"><span class=\"show-answer collapsed\" style=\"cursor: pointer\" data-target=\"qfs-id1165137645253\">Show Solution<\/span><\/p>\n<div id=\"qfs-id1165137645253\" class=\"hidden-answer\" style=\"display: none\"><span id=\"fs-id1165135653964\"><img decoding=\"async\" class=\"aligncenter\" src=\"https:\/\/s3-us-west-2.amazonaws.com\/courses-images\/wp-content\/uploads\/sites\/3896\/2019\/02\/08210004\/CNX_Precalc_Figure_01_06_207.jpg\" alt=\"Graph of an absolute function.\" \/><\/span><\/div>\n<\/div>\n<\/div>\n<\/div>\n<div id=\"fs-id1165137394585\">\n<div id=\"fs-id1165137394587\">\n<p id=\"fs-id1165135572124\">44. [latex]f\\left(x\\right)=-|x-1|-2[\/latex]<\/p>\n<\/div>\n<\/div>\n<div id=\"fs-id1165135335986\">\n<div id=\"fs-id1165137651575\">\n<p id=\"fs-id1165137651578\">45. [latex]f\\left(x\\right)=-|x+3|+4[\/latex]<\/p>\n<\/div>\n<div id=\"fs-id1165137434149\">\n<div class=\"qa-wrapper\" style=\"display: block\"><span class=\"show-answer collapsed\" style=\"cursor: pointer\" data-target=\"qfs-id1165137434149\">Show Solution<\/span><\/p>\n<div id=\"qfs-id1165137434149\" class=\"hidden-answer\" style=\"display: none\"><span id=\"fs-id1165137553071\"><img decoding=\"async\" class=\"aligncenter\" src=\"https:\/\/s3-us-west-2.amazonaws.com\/courses-images\/wp-content\/uploads\/sites\/3896\/2019\/02\/08210006\/CNX_Precalc_Figure_01_06_209.jpg\" alt=\"Graph of an absolute function.\" \/><\/span><\/div>\n<\/div>\n<\/div>\n<\/div>\n<div id=\"fs-id1165137705796\">\n<div id=\"fs-id1165137705798\">\n<p id=\"fs-id1165137469167\">46. [latex]f\\left(x\\right)=2|x+3|+1[\/latex]<\/p>\n<\/div>\n<\/div>\n<div id=\"fs-id1165137427199\">\n<div id=\"fs-id1165137619904\">\n<p id=\"fs-id1165137619906\">47. [latex]f\\left(x\\right)=3|x-2|+3[\/latex]<\/p>\n<\/div>\n<div id=\"fs-id1165137436399\">\n<div class=\"qa-wrapper\" style=\"display: block\"><span class=\"show-answer collapsed\" style=\"cursor: pointer\" data-target=\"qfs-id1165137436399\">Show Solution<\/span><\/p>\n<div id=\"qfs-id1165137436399\" class=\"hidden-answer\" style=\"display: none\"><span id=\"fs-id1165137410325\"><img decoding=\"async\" class=\"aligncenter\" src=\"https:\/\/s3-us-west-2.amazonaws.com\/courses-images\/wp-content\/uploads\/sites\/3896\/2019\/02\/08210009\/CNX_Precalc_Figure_01_06_211.jpg\" alt=\"Graph of an absolute function.\" \/><\/span><\/div>\n<\/div>\n<\/div>\n<\/div>\n<div id=\"fs-id1165137715460\">\n<div id=\"fs-id1165137715462\">\n<p id=\"fs-id1165137469722\">48. [latex]f\\left(x\\right)=|2x-4|-3[\/latex]<\/p>\n<\/div>\n<\/div>\n<div id=\"fs-id1165135258293\">\n<div id=\"fs-id1165135258295\">\n<p id=\"fs-id1165137452029\">49. [latex]f\\left(x\\right)=|3x+9|+2[\/latex]<\/p>\n<\/div>\n<div id=\"fs-id1165137433126\">\n<div class=\"qa-wrapper\" style=\"display: block\"><span class=\"show-answer collapsed\" style=\"cursor: pointer\" data-target=\"qfs-id1165137433126\">Show Solution<\/span><\/p>\n<div id=\"qfs-id1165137433126\" class=\"hidden-answer\" style=\"display: none\"><img decoding=\"async\" class=\"aligncenter\" src=\"https:\/\/s3-us-west-2.amazonaws.com\/courses-images\/wp-content\/uploads\/sites\/3896\/2019\/02\/08210011\/CNX_Precalc_Figure_01_06_213.jpg\" alt=\"Graph of an absolute function.\" \/><\/div>\n<\/div>\n<\/div>\n<\/div>\n<div id=\"fs-id1165137464095\">\n<div id=\"fs-id1165137464097\">\n<p id=\"fs-id1165137470140\">50. [latex]f\\left(x\\right)=-|x-1|-3[\/latex]<\/p>\n<\/div>\n<\/div>\n<div id=\"fs-id1165137443657\">\n<div id=\"fs-id1165137911316\">\n<p id=\"fs-id1165137911318\">51. [latex]f\\left(x\\right)=-|x+4|-3[\/latex]<\/p>\n<\/div>\n<div id=\"fs-id1165137399944\">\n<div class=\"qa-wrapper\" style=\"display: block\"><span class=\"show-answer collapsed\" style=\"cursor: pointer\" data-target=\"qfs-id1165137399944\">Show Solution<\/span><\/p>\n<div id=\"qfs-id1165137399944\" class=\"hidden-answer\" style=\"display: none\"><span id=\"fs-id1165137451010\"><img decoding=\"async\" class=\"aligncenter\" src=\"https:\/\/s3-us-west-2.amazonaws.com\/courses-images\/wp-content\/uploads\/sites\/3896\/2019\/02\/08210013\/CNX_Precalc_Figure_01_06_215.jpg\" alt=\"Graph of an absolute function.\" \/><\/span><\/div>\n<\/div>\n<\/div>\n<\/div>\n<div id=\"fs-id1165137803326\">\n<div id=\"fs-id1165137803328\">\n<p id=\"fs-id1165137824374\">52. [latex]f\\left(x\\right)=\\frac{1}{2}|x+4|-3[\/latex]<\/p>\n<\/div>\n<\/div>\n<\/div>\n<div id=\"fs-id1165137897208\" class=\"bc-section section\">\n<h4>Technology<\/h4>\n<div id=\"fs-id1165137749758\">\n<div id=\"fs-id1165137749760\">\n<p id=\"fs-id1165137460158\">53. Use a graphing utility to graph [latex]f\\left(x\\right)=10|x-2|[\/latex] on the viewing window [latex]\\left[0,4\\right].[\/latex] Identify the corresponding range. Show the graph.<\/p>\n<\/div>\n<div id=\"fs-id1165134042934\">\n<div class=\"qa-wrapper\" style=\"display: block\"><span class=\"show-answer collapsed\" style=\"cursor: pointer\" data-target=\"qfs-id1165134042934\">Show Solution<\/span><\/p>\n<div id=\"qfs-id1165134042934\" class=\"hidden-answer\" style=\"display: none\">\n<p id=\"fs-id1165134042935\">range:[latex]\\text{ }\\left[0,20\\right][\/latex]<\/p>\n<p><img decoding=\"async\" class=\"aligncenter\" src=\"https:\/\/s3-us-west-2.amazonaws.com\/courses-images\/wp-content\/uploads\/sites\/3896\/2019\/02\/08210015\/CNX_Precalc_Figure_01_06_217.jpg\" alt=\"Graph of an absolute function.\" \/><\/div>\n<\/div>\n<\/div>\n<\/div>\n<div id=\"fs-id1165137413783\">\n<div id=\"fs-id1165137434783\">\n<p id=\"fs-id1165137434785\">54. Use a graphing utility to graph[latex]\\text{ }f\\left(x\\right)=-100|x|+100\\text{ }[\/latex]on the viewing window[latex]\\text{ }\\left[-5,5\\right].\\text{ }[\/latex]Identify the corresponding range. Show the graph.<\/p>\n<\/div>\n<\/div>\n<p id=\"fs-id1165137831208\">For the following exercises, graph each function using a graphing utility. Specify the viewing window.<\/p>\n<div id=\"fs-id1165137762283\">\n<div id=\"fs-id1165135464843\">\n<p id=\"fs-id1165137724085\">55. [latex]f\\left(x\\right)=-0.1|0.1\\left(0.2-x\\right)|+0.3[\/latex]<\/p>\n<\/div>\n<div>\n<div class=\"qa-wrapper\" style=\"display: block\"><span class=\"show-answer collapsed\" style=\"cursor: pointer\" data-target=\"q258236\">Show Soution<\/span><\/p>\n<div id=\"q258236\" class=\"hidden-answer\" style=\"display: none\">\n<p id=\"fs-id1165137812573\">[latex]x\\text{-}[\/latex]intercepts:<\/p>\n<p><span id=\"fs-id1165137784866\"><img decoding=\"async\" class=\"aligncenter\" src=\"https:\/\/s3-us-west-2.amazonaws.com\/courses-images\/wp-content\/uploads\/sites\/3896\/2019\/02\/08210018\/CNX_Precalc_Figure_01_06_219.jpg\" alt=\"Graph of an absolute function.\" \/><\/span><\/p>\n<\/div>\n<\/div>\n<\/div>\n<\/div>\n<div id=\"eip-id1165134039354\">\n<div id=\"eip-id1165134039356\">\n<p id=\"fs-id1165137483195\">56. [latex]f\\left(x\\right)=4\u00d7{10}^{9}|x-\\left(5\u00d7{10}^{9}\\right)|+2\u00d7{10}^{9}[\/latex]<\/p>\n<\/div>\n<\/div>\n<\/div>\n<div id=\"fs-id1165137419467\" class=\"bc-section section\">\n<h4>Extensions<\/h4>\n<p id=\"fs-id1165137901338\">For the following exercises, solve the inequality.<\/p>\n<div id=\"fs-id1165137901341\">\n<div id=\"fs-id1165135397245\">\n<p id=\"fs-id1165135397247\">57. [latex]|-2x-\\frac{2}{3}\\left(x+1\\right)|+3>-1[\/latex]<\/p>\n<\/div>\n<div id=\"fs-id1165137662699\">\n<div class=\"qa-wrapper\" style=\"display: block\"><span class=\"show-answer collapsed\" style=\"cursor: pointer\" data-target=\"qfs-id1165137662699\">Show Solution<\/span><\/p>\n<div id=\"qfs-id1165137662699\" class=\"hidden-answer\" style=\"display: none\">\n<p id=\"fs-id1165137662701\">[latex]\\left(-\\infty ,\\infty \\right)[\/latex]<\/p>\n<\/div>\n<\/div>\n<\/div>\n<\/div>\n<div id=\"fs-id1165137434569\">\n<div id=\"fs-id1165137434570\">\n<p id=\"fs-id1165137434571\">58. If possible, find all values of [latex]a[\/latex] such that there are no [latex]x\\text{-}[\/latex]intercepts for [latex]f\\left(x\\right)=2|x+1|+a.[\/latex]<\/p>\n<\/div>\n<\/div>\n<div id=\"fs-id1165137639316\">\n<div id=\"fs-id1165137652958\">\n<p id=\"fs-id1165137652960\">59. If possible, find all values of[latex]\\text{ }a\\text{ }[\/latex]such that there are no [latex]\\text{ }y[\/latex]-intercepts for[latex]\\text{ }f\\left(x\\right)=2|x+1|+a.[\/latex]<\/p>\n<\/div>\n<div id=\"fs-id1165137648025\">\n<div class=\"qa-wrapper\" style=\"display: block\"><span class=\"show-answer collapsed\" style=\"cursor: pointer\" data-target=\"qfs-id1165137648025\">Show Solution<\/span><\/p>\n<div id=\"qfs-id1165137648025\" class=\"hidden-answer\" style=\"display: none\">\n<p id=\"fs-id1165137454792\">There is no solution for[latex]\\text{ }a\\text{ }[\/latex]that will keep the function from having a[latex]\\text{ }y[\/latex]-intercept. The absolute value function always crosses the [latex]\\text{ }y[\/latex]-intercept when[latex]\\text{ }x=0.[\/latex]<\/p>\n<\/div>\n<\/div>\n<\/div>\n<\/div>\n<\/div>\n<div id=\"fs-id1165135172151\" class=\"bc-section section\">\n<h4>Real-World Applications<\/h4>\n<div id=\"fs-id1165137641899\">\n<div id=\"fs-id1165137641901\">\n<p id=\"fs-id1165137459748\">60. Cities A and B are on the same east-west line. Assume that city A is located at the origin. If the distance from city A to city B is at least 100 miles and[latex]\\text{ }x\\text{ }[\/latex]represents the distance from city B to city A, express this using absolute value notation.<\/p>\n<\/div>\n<\/div>\n<div id=\"fs-id1165137812302\">\n<div id=\"fs-id1165137812304\">\n<p id=\"fs-id1165137431941\">61. The true proportion[latex]\\text{ }p\\text{ }[\/latex]of people who give a favorable rating to Congress is 8% with a margin of error of 1.5%. Describe this statement using an absolute value equation.<\/p>\n<\/div>\n<div id=\"fs-id1165135431083\">\n<div class=\"qa-wrapper\" style=\"display: block\"><span class=\"show-answer collapsed\" style=\"cursor: pointer\" data-target=\"qfs-id1165135431083\">Show Solution<\/span><\/p>\n<div id=\"qfs-id1165135431083\" class=\"hidden-answer\" style=\"display: none\">\n<p id=\"fs-id1165134042456\">[latex]|p-0.08|\\le 0.015[\/latex]<\/p>\n<\/div>\n<\/div>\n<\/div>\n<\/div>\n<div id=\"fs-id1165137598001\">\n<div id=\"fs-id1165137562568\">\n<p id=\"fs-id1165137562570\">62. Students who score within 18 points of the number 82 will pass a particular test. Write this statement using absolute value notation and use the variable[latex]\\text{ }x\\text{ }[\/latex]for the score.<\/p>\n<\/div>\n<\/div>\n<div id=\"fs-id1165137758810\">\n<div id=\"fs-id1165137758812\">\n<p id=\"fs-id1165135332394\">63. A machinist must produce a bearing that is within 0.01 inches of the correct diameter of 5.0 inches. Using[latex]\\text{ }x\\text{ }[\/latex]as the diameter of the bearing, write this statement using absolute value notation.<\/p>\n<\/div>\n<div id=\"fs-id1165135192953\">\n<div class=\"qa-wrapper\" style=\"display: block\"><span class=\"show-answer collapsed\" style=\"cursor: pointer\" data-target=\"qfs-id1165135192953\">Show Solution<\/span><\/p>\n<div id=\"qfs-id1165135192953\" class=\"hidden-answer\" style=\"display: none\">[latex]|x-5.0|\\le 0.01[\/latex]<\/div>\n<\/div>\n<\/div>\n<\/div>\n<div id=\"fs-id1165137732323\">\n<div id=\"fs-id1165137732325\">\n<p id=\"fs-id1165137673610\">64. The tolerance for a ball bearing is 0.01. If the true diameter of the bearing is to be 2.0 inches and the measured value of the diameter is[latex]\\text{ }x\\text{ }[\/latex]inches, express the tolerance using absolute value notation.<\/p>\n<\/div>\n<\/div>\n<\/div>\n<\/div>\n<div class=\"textbox shaded\">\n<h3>Glossary<\/h3>\n<dl id=\"fs-id1165135191341\">\n<dt>absolute value equation<\/dt>\n<dd id=\"fs-id1165137627032\">an equation of the form[latex]\\text{ }|A|=B,\\text{ }[\/latex]with[latex]\\text{ }B\\ge 0;\\text{ }[\/latex]it will have solutions when[latex]\\text{ }A=B\\text{ }[\/latex]or[latex]\\text{ }A=-B[\/latex]<\/dd>\n<\/dl>\n<dl id=\"fs-id1165137560214\">\n<dt>absolute value inequality<\/dt>\n<dd id=\"fs-id1165135173524\">a relationship in the form[latex]|A|<B,\\text{ }\\text{ }\\text{ }|A|\\le B,\\text{ }\\text{ }\\text{ }\\text{ }|A|>B,\\text{ }\\text{ }\\text{or }\\text{ }\\text{ }|A|\\ge B[\/latex]<\/dd>\n<\/dl>\n<\/div>\n\n\t\t\t <section class=\"citations-section\" role=\"contentinfo\">\n\t\t\t <h3>Candela Citations<\/h3>\n\t\t\t\t\t <div>\n\t\t\t\t\t\t <div id=\"citation-list-150\">\n\t\t\t\t\t\t\t <div class=\"licensing\"><div class=\"license-attribution-dropdown-subheading\">CC licensed content, Shared previously<\/div><ul class=\"citation-list\"><li>Absolute Value Functions. <strong>Authored by<\/strong>: Douglas Hoffman. <strong>Provided by<\/strong>: Openstax. <strong>Located at<\/strong>: <a target=\"_blank\" href=\"https:\/\/cnx.org\/contents\/l3_8ZlRi@1.94:IkN3_myo@8\/Absolute-Value-Functions\">https:\/\/cnx.org\/contents\/l3_8ZlRi@1.94:IkN3_myo@8\/Absolute-Value-Functions<\/a>. <strong>Project<\/strong>: Essential Precalcus, Part 1. <strong>License<\/strong>: <em><a target=\"_blank\" rel=\"license\" href=\"https:\/\/creativecommons.org\/licenses\/by\/4.0\/\">CC BY: Attribution<\/a><\/em><\/li><\/ul><\/div>\n\t\t\t\t\t\t <\/div>\n\t\t\t\t\t <\/div>\n\t\t\t <\/section>","protected":false},"author":311,"menu_order":1,"template":"","meta":{"_candela_citation":"[{\"type\":\"cc\",\"description\":\"Absolute Value Functions\",\"author\":\"Douglas Hoffman\",\"organization\":\"Openstax\",\"url\":\"https:\/\/cnx.org\/contents\/l3_8ZlRi@1.94:IkN3_myo@8\/Absolute-Value-Functions\",\"project\":\"Essential Precalcus, Part 1\",\"license\":\"cc-by\",\"license_terms\":\"\"}]","CANDELA_OUTCOMES_GUID":"","pb_show_title":"on","pb_short_title":"","pb_subtitle":"","pb_authors":[],"pb_section_license":""},"chapter-type":[],"contributor":[],"license":[],"class_list":["post-150","chapter","type-chapter","status-web-only","hentry"],"part":1458,"_links":{"self":[{"href":"https:\/\/courses.lumenlearning.com\/suny-dutchess-precalculus\/wp-json\/pressbooks\/v2\/chapters\/150","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/courses.lumenlearning.com\/suny-dutchess-precalculus\/wp-json\/pressbooks\/v2\/chapters"}],"about":[{"href":"https:\/\/courses.lumenlearning.com\/suny-dutchess-precalculus\/wp-json\/wp\/v2\/types\/chapter"}],"author":[{"embeddable":true,"href":"https:\/\/courses.lumenlearning.com\/suny-dutchess-precalculus\/wp-json\/wp\/v2\/users\/311"}],"version-history":[{"count":7,"href":"https:\/\/courses.lumenlearning.com\/suny-dutchess-precalculus\/wp-json\/pressbooks\/v2\/chapters\/150\/revisions"}],"predecessor-version":[{"id":2078,"href":"https:\/\/courses.lumenlearning.com\/suny-dutchess-precalculus\/wp-json\/pressbooks\/v2\/chapters\/150\/revisions\/2078"}],"part":[{"href":"https:\/\/courses.lumenlearning.com\/suny-dutchess-precalculus\/wp-json\/pressbooks\/v2\/parts\/1458"}],"metadata":[{"href":"https:\/\/courses.lumenlearning.com\/suny-dutchess-precalculus\/wp-json\/pressbooks\/v2\/chapters\/150\/metadata\/"}],"wp:attachment":[{"href":"https:\/\/courses.lumenlearning.com\/suny-dutchess-precalculus\/wp-json\/wp\/v2\/media?parent=150"}],"wp:term":[{"taxonomy":"chapter-type","embeddable":true,"href":"https:\/\/courses.lumenlearning.com\/suny-dutchess-precalculus\/wp-json\/pressbooks\/v2\/chapter-type?post=150"},{"taxonomy":"contributor","embeddable":true,"href":"https:\/\/courses.lumenlearning.com\/suny-dutchess-precalculus\/wp-json\/wp\/v2\/contributor?post=150"},{"taxonomy":"license","embeddable":true,"href":"https:\/\/courses.lumenlearning.com\/suny-dutchess-precalculus\/wp-json\/wp\/v2\/license?post=150"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}