Problem Set: Real Numbers

Classes of Real Numbers

Rational Numbers

In the following exercises, write as the ratio of two integers.

  1. 55
  2. 3.193.19
  1. 5151
  2. 319100319100
  1. 88
  2. 1.611.61
  1. 1212
  2. 9.2799.279
  1. 121121
  2. 9279100092791000
  1. 1616
  2. 4.3994.399

In the following exercises, determine which of the given numbers are rational and which are irrational.

0.750.75 , 0.22-30.22-3 , 1.39174... 1.39174... 

Rational: 0.75,0.22-30.75,0.22-3 . Irrational: 1.39174... 1.39174... 

0.360.36 , 0.94729\ldots 0.94729\ldots  , 2.52-82.52-8

0.-450.-45 , 1.919293... 1.919293...  , 3.593.59

Rational: 0.-450.-45 , 3.593.59 . Irrational: 1.919293... 1.919293... 

0.1-3,0.42982... 0.1-3,0.42982...  , 1.8751.875

In the following exercises, identify whether each number is rational or irrational.

  1. 2525
  2. 3030
  1. ⓐ rational
  2. ⓑ irrational
  1. 4444
  2. 4949
  1. 164164
  2. 169169
  1. ⓐ irrational
  2. ⓑ rational
  1. 225225
  2. 216216

Classifying Real Numbers

In the following exercises, determine whether each number is whole, integer, rational, irrational, and real.

88 , 0,1.95286....0,1.95286.... , 125125 , 3636 , 99

The table has seven rows and six columns. The first row is a header row that labels each column. The first column is labeled

99 , 349349 , 99 , 0.4-090.4-09 , 116116 , 77

100100 , 77 , 8383 , 11 , 0.770.77 , 314314

The table has seven rows and six columns. The first row is a header row that labels each column. The first column is labeled

EVERYDAY MATH

Field trip

All the 5th5th graders at Lincoln Elementary School will go on a field trip to the science museum. Counting all the children, teachers, and chaperones, there will be 147147 people. Each bus holds 4444 people.
ⓐ How many buses will be needed?
ⓑ Why must the answer be a whole number?
ⓒ Why shouldn’t you round the answer the usual way?

Child care

Serena wants to open a licensed child care center. Her state requires that there be no more than 12 children for each teacher. She would like her child care center to serve 40 children.
ⓐ How many teachers will be needed?
ⓑ Why must the answer be a whole number?
ⓒ Why shouldn’t you round the answer the usual way?

ⓐ 4
ⓑ Teachers cannot be divided
ⓒ It would result in a lower number.

 

WRITING EXERCISES

In your own words, explain the difference between a rational number and an irrational number.

Explain how the sets of numbers (counting, whole, integer, rational, irrationals, reals) are related to each other.

Answers will vary.

 

Using the Commutative and Associative Properties

In the following exercises, use the commutative properties to rewrite the given expression.

8+9=___

7+6=___

7 + 6 = 6 + 7

8(12)=___

7(13)=___

7(−13) = (−13)7

(-19)(-14)=___

(12)(18)=___

(−12)(−18) = (−18)(−12)

-11+8=___

-15+7=___

−15 + 7 = 7 + (−15)

x+4=___

y+1=___

y + 1 = 1 + y

-2a=___

-3m=___

−3m = m(−3)

In the following exercises, use the associative properties to rewrite the given expression.

(11+9)+14=___

(21+14)+9=___

(21 + 14) + 9 = 21 + (14 + 9)

(125)7=___

(146)9=___

(14 · 6) · 9 = 14(6 · 9)

(7+9)+8=___

(2+6)+7=___

(−2 + 6) + 7 = −2 + (6 + 7)

(1645)15=___

(1323)18=___

(1323)18=13(2318)

3(4x)=___

4(7x)=___

4(7x) = (4 · 7)x

(12+x)+28=___

(17+y)+33=___

(17 + y) + 33 = 17 + (y + 33)

Evaluate Expressions using the Commutative and Associative Properties

In the following exercises, evaluate each expression for the given value.

If y=58, evaluate:

y+0.49+(y)
y+(y)+0.49

If z=78, evaluate:

z+0.97+(z)
z+(z)+0.97

  1. ⓐ 0.97
  2. ⓑ 0.97

If c=114, evaluate:

c+3.125+(c)
c+(c)+3.125

If d=94, evaluate:

d+2.375+(d)
d+(d)+2.375

ⓐ 2.375
ⓑ 2.375

If j=11, evaluate:

56(65j)
(5665)j

If k=21, evaluate:

413(134k)
(413134)k

ⓐ 21
ⓑ 21

If m=25, evaluate:

37(73m)
(3773)m

If n=8, evaluate:

521(215n)
(521215)n

ⓐ −8
ⓑ −8

Simplify Expressions Using the Commutative and Associative Properties

In the following exercises, simplify.

45a+15+45a

9y+23+(9y)

23

12+78+(12)

25+512+(25)

512

3204911203

13182571813

257

712917247

3101323503

6523

24738

361149

−176

(56+815)+715

(112+49)+59

1312

513+34+14

815+57+27

2315

(4.33p+1.09p)+3.91p

(5.89d+2.75d)+1.25d

9.89d

17(0.25)(4)

36(0.2)(5)

36

[2.48(12)](0.5)

[9.731(4)](0.75)

29.193

7(4a)

9(8w)

72w

15(5m)

23(2n)

−46n

12(56p)

20(35q)

12q

14x+19y+25x+3y

15u+11v+27u+19v

42u + 30v

43m+(12n)+ (16m)+(9n)

22p+17q+(35p)+(27q)

−57p + (−10q)

38g+112h+78g+512h

56a+310b+16a+910b

a+65b

6.8p+9.14q+(4.37p)+(0.88q)

9.6m+7.22n+(2.19m)+(0.65n)

7.41m + 6.57n

EVERYDAY MATH

Stamps

Allie and Loren need to buy stamps. Allie needs four $0.49 stamps and nine $0.02 stamps. Loren needs eight $0.49 stamps and three $0.02 stamps.
ⓐ How much will Allie’s stamps cost?
ⓑ How much will Loren’s stamps cost?
ⓒ What is the total cost of the girls’ stamps?
ⓓ How many $0.49 stamps do the girls need altogether? How much will they cost?
ⓔ How many $0.02 stamps do the girls need altogether? How much will they cost?

Counting Cash

Grant is totaling up the cash from a fundraising dinner. In one envelope, he has twenty-three $5 bills, eighteen $10 bills, and thirty-four $20 bills. In another envelope, he has fourteen $5 bills, nine $10 bills, and twenty-seven $20 bills.
ⓐ How much money is in the first envelope?
ⓑ How much money is in the second envelope?
ⓒ What is the total value of all the cash?
ⓓ What is the value of all the $5 bills?
ⓔ What is the value of all $10 bills?
ⓕ What is the value of all $20 bills?

  1. ⓐ $975
  2. ⓑ $700
  3. ⓒ $1675
  4. ⓓ $185
  5. ⓔ $270
  6. ⓕ $1220

 

WRITING EXERCISES

In your own words, state the Commutative Property of Addition and explain why it is useful.

In your own words, state the Associative Property of Multiplication and explain why it is useful.

Answers will vary.

 

Using the Distributive Property

Simplify Expressions Using the Distributive Property

In the following exercises, simplify using the distributive property.

4(x+8)

3(a+9)

3a + 27

8(4y+9)

9(3w+7)

27w + 63

6(c13)

7(y13)

7y − 91

7(3p8)

5(7u4)

35u − 20

12(n+8)

13(u+9)

13u+3

14(3q+12)

15(4m+20)

45m+4

9(59y13)

10(310x25)

3x − 4

12(14+23r)

12(16+34s)

2 + 9s

r(s18)

u(v10)

uv − 10u

(y+4)p

(a+7)x

ax + 7x

2(y+13)

3(a+11)

−3a − 33

7(4p+1)

9(9a+4)

−81a − 36

3(x6)

4(q7)

−4q + 28

9(3a7)

6(7x8)

−42x + 48

(r+7)

(q+11)

q − 11

(3x7)

(5p4)

−5p + 4

5+9(n6)

12+8(u1)

8u + 4

163(y+8)

184(x+2)

−4x + 10

411(3c2)

96(7n5)

−42n + 39

22(a+3)

8(r7)

r + 15

12(u+10)

4(c10)

c + 6

(5m3)(m+7)

(4y1)(y2)

3y + 1

5(2n+9)+12(n3)

9(5u+8)+2(u6)

47u + 60

9(8x3)(2)

4(6x1)(8)

24x + 4

14(c1)8(c6)

11(n7)5(n1)

6n − 72

6(7y+8)(30y15)

7(3n+9)(4n13)

17n + 76

Evaluate Expressions Using the Distributive Property

In the following exercises, evaluate both expressions for the given value.

If v=2, evaluate

6(4v+7)
64v+67

If u=1, evaluate

8(5u+12)
85u+812

ⓐ 56
ⓑ 56

If n=23, evaluate

3(n+56)
3n+356

If y=34, evaluate

4(y+38)
4y+438

92
92

If y=712, evaluate

3(4y+15)
34y+(3)15

If p=2330, evaluate

6(5p+11)
65p+(6)11

ⓐ −89
ⓑ −89

If m=0.4, evaluate

10(3m0.9)
103m(10)(0.9)

If n=0.75, evaluate

100(5n+1.5)
1005n+(100)(1.5)

ⓐ −525
ⓑ −525

If y=25, evaluate

(y25)
y+25

If w=80, evaluate

(w80)
w+80

ⓐ 160
ⓑ 160

If p=0.19, evaluate

(p+0.72)
p0.72

If q=0.55, evaluate

(q+0.48)
q0.48

ⓐ −1.03
ⓑ −1.03

EVERYDAY MATH

Buying by the case

Joe can buy his favorite ice tea at a convenience store for $1.99 per bottle. At the grocery store, he can buy a case of 12 bottles for $23.88.
ⓐ Use the distributive property to find the cost of 12 bottles bought individually at the convenience store. (Hint: notice that $1.99 is $2$0.01. )
ⓑ Is it a bargain to buy the iced tea at the grocery store by the case?

Multi-pack purchase

Adele’s shampoo sells for $3.97 per bottle at the drug store. At the warehouse store, the same shampoo is sold as a 3pack for $10.49.
ⓐ Show how you can use the distributive property to find the cost of 3 bottles bought individually at the drug store.
ⓑ How much would Adele save by buying the 3pack at the warehouse store?

ⓐ 3(4 − 0.03) = 11.91
ⓑ $1.42

 

WRITING EXERCISES

Simplify 8(x14) using the distributive property and explain each step.

Explain how you can multiply 4($5.97) without paper or a calculator by thinking of $5.97 as 60.03 and then using the distributive property.

 

Properties of Identity, Inverses, and Zero

In the following exercises, identify whether each example is using the identity property of addition or multiplication.

101+0=101

35(1)=35

identity property of multiplication

91=9

0+64=64

identity property of addition

Use the Inverse Properties of Addition and Multiplication
In the following exercises, find the multiplicative inverse.

8

14

114

17

19

119

712

813

138

310

512

125

0.8

0.4

52

0.2

0.5

−2

Use the Properties of Zero

In the following exercises, simplify using the properties of zero.

480

06

0

30

220

0

0÷1112

60

undefined

03

0÷715

0

0815

(3.14)(0)

0

5.72÷0

1100

undefined

Simplify Expressions using the Properties of Identities, Inverses, and Zero

In the following exercises, simplify using the properties of identities, inverses, and zero.

19a+4419a

27c+1627c

16

38+11r38

92+31s92

31s

10(0.1d)

100(0.01p)

p

5(0.6q)

40(0.05n)

2n

0r+20 , where r20

0s+13 , where s13

0

0u4.99 , where u4.99

0v65.1 , where v65.1

0

0÷(x12) , where x12

0÷(y16) , where y16

0

325a0 , where 325a0

289b0 , where 289b0

undefined

2.1+0.4c0 , where 2.1+0.4c0

1.75+9f0 , where 1.75+9f0

undefined

(34+910m)÷0 , where 34+910m0

(516n37)÷0 , where 516n370

undefined

910109(18p21)

5775(20q35)

20q − 35

1535(4d+10)

1856(15h+24)

225h + 360

EVERYDAY MATH

Insurance copayment

Carrie had to have 5 fillings done. Each filling cost $80. Her dental insurance required her to pay 20 of the cost. Calculate Carrie’s cost
ⓐ by finding her copay for each filling, then finding her total cost for 5 fillings, and
ⓑ by multiplying 5(0.20)(80).
ⓒ Which of the Properties of Real Numbers did you use for part (b)?

Cooking time

Helen bought a 24-pound turkey for her family’s Thanksgiving dinner and wants to know what time to put the turkey in the oven. She wants to allow 20 minutes per pound cooking time.
ⓐ Calculate the length of time needed to roast the turkey by multiplying 2420 to find the number of minutes and then multiplying the product by 160 to convert minutes into hours.
ⓑ Multiply 24(20160).
ⓒ Which of the Properties of Real Numbers allows you to multiply 24(20160) instead of (2420)160?

ⓐ 8 hours
ⓑ 8
ⓒ associative property of multiplication

 

WRITING EXERCISES

In your own words, describe the difference between the additive inverse and the multiplicative inverse of a number.

How can the use of the properties of real numbers make it easier to simplify expressions?

Answers will vary.

 

Determine Whether a Number is a Solution of an Equation

In the following exercises, determine whether each number is a solution of the given equation.

4x2=6

x=2
x=1
x=2

  1. ⓐ no
  2. ⓑ yes
  3. ⓒ no

4y10=14

y=6
y=1
y=1

9a+27=63

a=6
a=6
a=10

  1. ⓐ no
  2. ⓑ no
  3. ⓒ yes

7c+42=56

c=2
c=2
c=14

Solve Equations Using the Addition and Subtraction Properties of Equality

In the following exercises, solve for the unknown.

n+12=5

−7

m+16=2

p+9=8

−17

q+5=6

u3=7

−4

v7=8

h10=4

6

k9=5

x+(2)=18

−16

y+(3)=10

r(5)=9

−14

s(2)=11

Model the Division Property of Equality

In the following exercises, write the equation modeled by the envelopes and counters and then solve it.

No Alt Text

3x = 6; x = 2

No Alt Text

No Alt Text

2x = 8; x = 4

No Alt Text

Solve Equations Using the Division Property of Equality

In the following exercises, solve each equation using the division property of equality and check the solution.

5x=45

9

4p=64

7c=56

−8

9x=54

14p=42

3

8m=40

120=10q

−12

75=15y

24x=480

20

18n=540

3z=0

0

4u=0

Translate to an Equation and Solve

In the following exercises, translate and solve.

Four more than n is equal to 1.

n + 4 = 1; n = −3

Nine more than m is equal to 5.

The sum of eight and p is 3 .

8 + p = −3; p = −11

The sum of two and q is 7 .

The difference of a and three is 14 .

a − 3 = −14; a = −11

The difference of b and 5 is 2 .

The number −42 is the product of −7 and x .

−42 = −7x; x = 6

The number −54 is the product of −9 and y .

The product of f and −15 is 75.

f(−15) = 75; f = 5

The product of g and −18 is 36.

−6 plus c is equal to 4.

−6 + c = 4; c = 10

−2 plus d is equal to 1.

Nine less than n is −4.

m − 9 = −4; m = 5

Thirteen less than n is 10 .

Mixed Practice

In the following exercises, solve.

  1. x+2=10
  2. 2x=10
  1. ⓐ 8
  2. ⓑ 5
  1. y+6=12
  2. 6y=12
  1. 3p=27
  2. p3=27
  1. ⓐ −9
  2. ⓑ 30
  1. 2q=34
  2. q2=34

a4=16

20

b1=11

8m=56

7

6n=48

39=u+13

−52

100=v+25

11r=99

−9

15s=300

100=20d

5

250=25n

49=x7

−42

64=y4

EVERYDAY MATH

Cookie packaging

A package of 51 cookies has 3 equal rows of cookies. Find the number of cookies in each row, c, by solving the equation 3c=51.

17 cookies

Kindergarten class

Connie’s kindergarten class has 24 children. She wants them to get into 4 equal groups. Find the number of children in each group, g, by solving the equation 4g=24.

 

WRITING EXERCISES

Is modeling the Division Property of Equality with envelopes and counters helpful to understanding how to solve the equation 3x=15? Explain why or why not.

Sample answer: It is helpful because it shows how the counters can be divided among the envelopes.

Suppose you are using envelopes and counters to model solving the equations x+4=12 and 4x=12. Explain how you would solve each equation.

Frida started to solve the equation 3x=36 by adding 3 to both sides. Explain why Frida’s method will not solve the equation.

Sample answer: The operation used in the equation is multiplication. The inverse of multiplication is division, not addition.

Raoul started to solve the equation 4y=40 by subtracting 4 from both sides. Explain why Raoul’s method will not solve the equation.

 

Chapter Review Exercises

Introduction to integers

Locate Positive and Negative Numbers on the Number Line

In the following exercises, locate and label the integer on the number line.

5

This figure is a number line. It is scaled from negative 10 to 10 in increments of 2. There is a point at 5.

5

3

This figure is a number line. It is scaled from negative 10 to 10 in increments of 2. There is a point at negative 3.

3

8

This figure is a number line. It is scaled from negative 10 to 10 in increments of 2. There is a point at negative 8.

7

Order Positive and Negative Numbers

In the following exercises, order each of the following pairs of numbers, using <; or >.

4__8

<

6__3

5__10

>

9__4

2__7

>

3__1

Find Opposites

In the following exercises, find the opposite of each number.

6

−6

2

4

4

3

In the following exercises, simplify.

  1. (8)
  2. (8)
  1. ⓐ −8
  2. ⓑ 8
  1. (9)
  2. (9)

In the following exercises, evaluate.

x,when

x=32
x=32

  1. ⓐ −32
  2. ⓑ 32

n,when

n=20
n=20

 

 

ABSOLUTE VALUES

Simplify Absolute Values

In the following exercises, simplify.

|21|

21

|42|

|36|

36

|15|

|0|

0

|75|

In the following exercises, evaluate.

|x|whenx=14

14

|r|whenr=27

|y|wheny=33

−33

|-n|whenn=4

In the following exercises, fill in <,>,or= for each of the following pairs of numbers.

|4|__4

<

2__|2|

|6|__6

=

|9|__|9|

In the following exercises, simplify.

(55)and|55|

−55; −55

(48)and|48|

|125|

7

|9+7|

6|9|

54

|148||2|

|93||512|

−1

5+4|153|

 

 

Translate Phrases to Expressions with Integers

In the following exercises, translate each of the following phrases into expressions with positive or negative numbers.

the opposite of 16

−16

the opposite of 8

negative 3

−3

19 minus negative 12

a temperature of 10 below zero

−10°

an elevation of 85 feet below sea level

Add Integers

Model Addition of Integers

In the following exercises, model the following to find the sum.

3+7

10

2+6

5+(4)

1

3+(6)

Simplify Expressions with Integers

In the following exercises, simplify each expression.

14+82

96

33+(67)

75+25

−50

54+(28)

11+(15)+3

−1

19+(42)+12

3+6(1+5)

21

10+4(3+7)

Evaluate Variable Expressions with Integers

In the following exercises, evaluate each expression.

n+4when

n=1
n=20

  1. ⓐ 3
  2. ⓑ −16

x+(9)when

x=3
x=3

(x+y)3whenx=4,y=1

−27

(u+v)2whenu=4,v=11

 

 

TRANSLATE WORD PHRASES TO ALGEBRAIC EXPRESSIONS

In the following exercises, translate each phrase into an algebraic expression and then simplify.

the sum of -8 and 2

−8 + 2 = −6

4 more than -12

10 more than the sum of -5 and -6

10 + [−5 + (−6)] = −1

the sum of3and5,increased by 18

 

 

Add Integers in Applications

In the following exercises, solve.

Temperature

On Monday, the high temperature in Denver was -4 degrees. Tuesday’s high temperature was 20 degrees more. What was the high temperature on Tuesday?

16 degrees

Credit

Frida owed $75 on her credit card. Then she charged $21 more. What was her new balance?

Subtract Integers

Model Subtraction of Integers

In the following exercises, model the following.

61

This figure is a row of 6 light pink circles, representing positive counters. The first one is circled.

5

4(3)

2(5)

This figure shows 2 rows. The first row shows 7 light pink circles, representing positive counters. The second row shows 5 dark pink circles, representing negative counters. The entire second row is circled.

7

14

Simplify Expressions with Integers

In the following exercises, simplify each expression.

2416

8

19(9)

317

−38

40(11)

52(17)23

−58

25(39)

(17)(38)

−1

3272

Evaluate Variable Expressions with Integers
In the following exercises, evaluate each expression.

x7when

x=5
x=4

  1. ⓐ −2
  2. ⓑ −11

10ywhen

y=15
y=16

2n2n+5whenn=4

41

153u2whenu=5

Translate Phrases to Algebraic Expressions

In the following exercises, translate each phrase into an algebraic expression and then simplify.

the difference of 12and5

−12 − 5 = −17

subtract 23 from 50

Subtract Integers in Applications

In the following exercises, solve the given applications.

Temperature

One morning the temperature in Bangor, Maine was 18 degrees. By afternoon, it had dropped 20 degrees. What was the afternoon temperature?

−2 degrees

Temperature

On January 4, the high temperature in Laredo, Texas was 78 degrees, and the high in Houlton, Maine was 28degrees. What was the difference in temperature of Laredo and Houlton?

 

Multiply and Divide Integers

Multiply Integers
In the following exercises, multiply.

94

−36

5(7)

(11)(11)

121

16

Divide Integers
In the following exercises, divide.

56÷(8)

−7

120÷(6)

96÷12

−8

96÷(16)

45÷(1)

−45

162÷(1)

 

 

Simplify Expressions with Integers

In the following exercises, simplify each expression.

5(9)3(12)

−9

(2)5

34

−81

(3)(4)(5)(6)

424(69)

54

(815)(93)

2(18)÷9

4

45÷(3)12

 

 

Evaluate Variable Expressions with Integers

In the following exercises, evaluate each expression.

7x3whenx=9

−66

162nwhenn=8

5a+8bwhena=2,b=6

−58

x2+5x+4whenx=3

 

 

 

Translate Word Phrases to Algebraic Expressions

In the following exercises, translate to an algebraic expression and simplify if possible.

the product of 12 and 6

−12(6) = −72

the quotient of 3 and the sum of 7 and s

Solve Equations using Integers; The Division Property of Equality
Determine Whether a Number is a Solution of an Equation
In the following exercises, determine whether each number is a solution of the given equation.

5x10=35

x=9
x=5
x=5

  1. ⓐ no
  2. ⓑ yes
  3. ⓒ no

8u+24=32

u=7
u=1
u=7

Using the Addition and Subtraction Properties of Equality
In the following exercises, solve.

a+14=2

−12

b9=15

−6

c+(10)=17

−7

d(6)=26

−32

 

 

Model the Division Property of Equality

In the following exercises, write the equation modeled by the envelopes and counters. Then solve it.

This image has two columns. In the first column there are three envelopes. In the second column there are two vertical rows. The first row includes five blue circles, the second row includes four blue circles.

3x = 9; x = 3>

This figure has two columns. In the first column there are two envelopes. In the second column there are two vertical rows, each includes four blue circles.

Solve Equations Using the Division Property of Equality
In the following exercises, solve each equation using the division property of equality and check the solution.

8p=72

9

12q=48

16r=64

4

5s=100

Translate to an Equation and Solve.
In the following exercises, translate and solve.

The product of -6 andyis42

−6y = −42; y = 7

The difference ofzand -13 is -18.

Four more than m is 48.

m + 4 = −48; m = −52

The product of -21 andnis 63.

 

Everyday Math

Describe how you have used two topics from this chapter in your life outside of your math class during the past month.

 

Chapter Practice Test

Locate and label 0,2,4, and 1 on a number line.

In the following exercises, compare the numbers, using <or>or=.

  1. 6__3
  2. 1__4
  1. ⓐ <
  2. ⓑ >
  1. 5__|5|
  2. |2|__2

In the following exercises, find the opposite of each number.

  1. 7
  2. 8
  1. ⓐ 7
  2. ⓑ −8

In the following exercises, simplify.

(22)

|49|

5

8+6

15+(12)

−27

7(3)

10(56)

11

38

6(9)

54

70÷(7)

(2)3

−8

42

163(57)

22

|216||8|

In the following exercises, evaluate.

35awhena=4

39

(2r)2whenr=3

3m2nwhenm=6,n=8

34

|y|wheny=17

In the following exercises, translate each phrase into an algebraic expression and then simplify, if possible.

the difference of −7 and −4

−7 − (−4) = −3

the quotient of 25 and the sum of m and n.

In the following exercises, solve.

Early one morning, the temperature in Syracuse was 8^\circ F. By noon, it had risen 12^\circ . What was the temperature at noon?

4°F

Collette owed $128 on her credit card. Then she charged $65. What was her new balance?

In the following exercises, solve.

n+6=5

n = −1

p11=4

9r=54

r = 6

In the following exercises, translate and solve.

The product of 15 andxis 75.

Eight less thanyis -32.

y − 8 = −32; y = −24