9.3 – Introduction to Using Intercepts to Graph Lines

What you’ll learn to do: Plot lines on the rectangular coordinate system using x- and y-intercepts

One of the easiest ways to graph a line is by using the x- and y- intercepts as two of your points.

In this section, we will learn how to:

  • Identify the x- and y-intercepts on a graph and as ordered pairs
  • Find the intercepts from an equation of a line
  • Graph a linear equation using x and y-intercepts

Before you get started in this module, try a few practice problems and review prior concepts.

readiness quiz

1)

Solve: [latex]3x+4y=-12[/latex] for [latex]x[/latex] when [latex]y=0[/latex].

Solution: [latex]x=-4[/latex]

2)

If you missed this problem, review this example.

Name the ordered pair of each point shown:The graph shows the x y-coordinate plane. The x and y-axis each run from -7 to 7. The point

3)

If you missed this problem, review the example below.

Determine which ordered pairs are solutions of the equation [latex]x+4y=8\text{:}[/latex]

1. [latex]\left(0,2\right)[/latex]
2. [latex]\left(2,-4\right)[/latex]
3. [latex]\left(-4,3\right)[/latex]