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Prealgebra 2e

Chapter 8

Prealgebra 2eChapter 8
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  1. Preface
  2. 1 Whole Numbers
    1. Introduction
    2. 1.1 Introduction to Whole Numbers
    3. 1.2 Add Whole Numbers
    4. 1.3 Subtract Whole Numbers
    5. 1.4 Multiply Whole Numbers
    6. 1.5 Divide Whole Numbers
    7. Key Terms
    8. Key Concepts
    9. Exercises
      1. Review Exercises
      2. Practice Test
  3. 2 The Language of Algebra
    1. Introduction to the Language of Algebra
    2. 2.1 Use the Language of Algebra
    3. 2.2 Evaluate, Simplify, and Translate Expressions
    4. 2.3 Solving Equations Using the Subtraction and Addition Properties of Equality
    5. 2.4 Find Multiples and Factors
    6. 2.5 Prime Factorization and the Least Common Multiple
    7. Key Terms
    8. Key Concepts
    9. Exercises
      1. Review Exercises
      2. Practice Test
  4. 3 Integers
    1. Introduction to Integers
    2. 3.1 Introduction to Integers
    3. 3.2 Add Integers
    4. 3.3 Subtract Integers
    5. 3.4 Multiply and Divide Integers
    6. 3.5 Solve Equations Using Integers; The Division Property of Equality
    7. Key Terms
    8. Key Concepts
    9. Exercises
      1. Review Exercises
      2. Practice Test
  5. 4 Fractions
    1. Introduction to Fractions
    2. 4.1 Visualize Fractions
    3. 4.2 Multiply and Divide Fractions
    4. 4.3 Multiply and Divide Mixed Numbers and Complex Fractions
    5. 4.4 Add and Subtract Fractions with Common Denominators
    6. 4.5 Add and Subtract Fractions with Different Denominators
    7. 4.6 Add and Subtract Mixed Numbers
    8. 4.7 Solve Equations with Fractions
    9. Key Terms
    10. Key Concepts
    11. Exercises
      1. Review Exercises
      2. Practice Test
  6. 5 Decimals
    1. Introduction to Decimals
    2. 5.1 Decimals
    3. 5.2 Decimal Operations
    4. 5.3 Decimals and Fractions
    5. 5.4 Solve Equations with Decimals
    6. 5.5 Averages and Probability
    7. 5.6 Ratios and Rate
    8. 5.7 Simplify and Use Square Roots
    9. Key Terms
    10. Key Concepts
    11. Exercises
      1. Review Exercises
      2. Practice Test
  7. 6 Percents
    1. Introduction to Percents
    2. 6.1 Understand Percent
    3. 6.2 Solve General Applications of Percent
    4. 6.3 Solve Sales Tax, Commission, and Discount Applications
    5. 6.4 Solve Simple Interest Applications
    6. 6.5 Solve Proportions and their Applications
    7. Key Terms
    8. Key Concepts
    9. Exercises
      1. Review Exercises
      2. Practice Test
  8. 7 The Properties of Real Numbers
    1. Introduction to the Properties of Real Numbers
    2. 7.1 Rational and Irrational Numbers
    3. 7.2 Commutative and Associative Properties
    4. 7.3 Distributive Property
    5. 7.4 Properties of Identity, Inverses, and Zero
    6. 7.5 Systems of Measurement
    7. Key Terms
    8. Key Concepts
    9. Exercises
      1. Review Exercises
      2. Practice Test
  9. 8 Solving Linear Equations
    1. Introduction to Solving Linear Equations
    2. 8.1 Solve Equations Using the Subtraction and Addition Properties of Equality
    3. 8.2 Solve Equations Using the Division and Multiplication Properties of Equality
    4. 8.3 Solve Equations with Variables and Constants on Both Sides
    5. 8.4 Solve Equations with Fraction or Decimal Coefficients
    6. Key Terms
    7. Key Concepts
    8. Exercises
      1. Review Exercises
      2. Practice Test
  10. 9 Math Models and Geometry
    1. Introduction
    2. 9.1 Use a Problem Solving Strategy
    3. 9.2 Solve Money Applications
    4. 9.3 Use Properties of Angles, Triangles, and the Pythagorean Theorem
    5. 9.4 Use Properties of Rectangles, Triangles, and Trapezoids
    6. 9.5 Solve Geometry Applications: Circles and Irregular Figures
    7. 9.6 Solve Geometry Applications: Volume and Surface Area
    8. 9.7 Solve a Formula for a Specific Variable
    9. Key Terms
    10. Key Concepts
    11. Exercises
      1. Review Exercises
      2. Practice Test
  11. 10 Polynomials
    1. Introduction to Polynomials
    2. 10.1 Add and Subtract Polynomials
    3. 10.2 Use Multiplication Properties of Exponents
    4. 10.3 Multiply Polynomials
    5. 10.4 Divide Monomials
    6. 10.5 Integer Exponents and Scientific Notation
    7. 10.6 Introduction to Factoring Polynomials
    8. Key Terms
    9. Key Concepts
    10. Exercises
      1. Review Exercises
      2. Practice Test
  12. 11 Graphs
    1. Graphs
    2. 11.1 Use the Rectangular Coordinate System
    3. 11.2 Graphing Linear Equations
    4. 11.3 Graphing with Intercepts
    5. 11.4 Understand Slope of a Line
    6. Key Terms
    7. Key Concepts
    8. Exercises
      1. Review Exercises
      2. Practice Test
  13. A | Cumulative Review
  14. B | Powers and Roots Tables
  15. C | Geometric Formulas
  16. Answer Key
    1. Chapter 1
    2. Chapter 2
    3. Chapter 3
    4. Chapter 4
    5. Chapter 5
    6. Chapter 6
    7. Chapter 7
    8. Chapter 8
    9. Chapter 9
    10. Chapter 10
    11. Chapter 11
  17. Index

Be Prepared

8.1

2828

8.2

x5x5

8.3

yes

8.4

11

8.5

8383

8.6

2525

8.7

4y4y

8.8

44

8.9

2121

8.10

33

8.11

1212

8.12

478478

Try It

8.1

no

8.2

no

8.3

x = −16

8.4

x = −20

8.5

n = −1

8.6

x = −4

8.7

p=76p=76

8.8

q=23q=23

8.9

b = 6.4

8.10

c = 14

8.11

y = 15

8.12

z = 2

8.13

p = 5

8.14

q = −16

8.15

h = −1

8.16

x = 1

8.17

x + 11 = 41; x = 30

8.18

y − 12 = 51; y = 63

8.19

4x − 3x = 14; x = 14

8.20

7a − 6a = −8; a = −8

8.21

a + 6 = 13; Athena weighs 7 pounds.

8.22

26 + h = 68; Henry has 42 books.

8.23

19,875 = s − 1025; the sticker price is $20,900.

8.24

7.75 = n − 3.25; the price at night is $11.00.

8.25

y = −16

8.26

z = −13

8.27

b = 144

8.28

c = 128

8.29

k = −8

8.30

g = −3

8.31

n = 35

8.32

y = 18

8.33

x = 2

8.34

n = −5

8.35

c = −3

8.36

x=47x=47

8.37

n = −6

8.38

n = −5

8.39

x = −4

8.40

a = −8

8.41

y = 5

8.42

m = 9

8.43

n = 10

8.44

c = 1

8.45

p = −7

8.46

m = −3

8.47

j = 2

8.48

h = 1

8.49

x = −1

8.50

y = 4

8.51

q = 1

8.52

n = 1

8.53

a = −5

8.54

k = −6

8.55

x = 10

8.56

y = −3

8.57

x = −5

8.58

y = −5

8.59

x = 4

8.60

y = 1

8.61

y = −6

8.62

z = 8

8.63

a = 2

8.64

n = 2

8.65

j=53j=53

8.66

k=52k=52

8.67

p = −2

8.68

q = −8

8.69

u = 2

8.70

x = 4

8.71

n = 1

8.72

m = −1

8.73

x=12x=12

8.74

y = 3

8.75

v = 40

8.76

u = −12

8.77

a = −2

8.78

c = −2

8.79

p = −4

8.80

q = 2

8.81

n = 2

8.82

m = −1

8.83

x = 20

8.84

x = 10

8.85

h = 12

8.86

k = −1

8.87

n = 9

8.88

d = 16

Section 8.1 Exercises

1.

yes

3.

no

5.

x = 5

7.

b=12b=12

9.

p = −11.7

11.

a = 10

13.

x=73x=73

15.

y = 13.8

17.

x = −27

19.

q=14q=14

21.

y=2720y=2720

23.

m = 17

25.

x = 8

27.

n = −20

29.

y = 2

31.

w = −1.7

33.

x = −2

35.

m = −4

37.

k = 6

39.

c = −41

41.

y = 28

43.

x + (−5) = 33; x = 38

45.

y − 3 = −19; y = −16

47.

p + 8 = 52; p = 44

49.

5c − 4c = 60; c = 60

51.

f13=112;f=512f13=112;f=512

53.

−9m + 10m = −25; m = −25

55.

Let p equal the number of pages read in the Psychology book. 41 + p = 54. Jeff read 13 pages in his Psychology book.

57.

Let d equal the daughter’s age. d = 12 − 5. Eva’s daughter’s age is 7 years old.

59.

21 pounds

61.

100.5 degrees

63.

$121.19

65.

d=1324d=1324

67.

Answers will vary.

Section 8.2 Exercises

69.

p = 9

71.

x = 3

73.

y = −6

75.

m = 7

77.

a = 15

79.

x = 0

81.

z = 28

83.

c = 36

85.

q = −48

87.

p = 80

89.

r = 25

91.

x = −32

93.

q=52q=52

95.

y = −1

97.

m = −5

99.

t=52t=52

101.

q = 24

103.

p = 56

105.

6 children

107.

$1.08

109.

42 yards

111.

Answer will vary.

Section 8.3 Exercises

113.

x = 6

115.

y = 6

117.

m = −8

119.

b = −8

121.

x = −4

123.

q = −2

125.

k = −11

127.

x = 9

129.

b = −3

131.

z = 3

133.

x=34x=34

135.

r = −2

137.

x = 19

139.

f = 7

141.

q = −5

143.

c = −4

145.

x = 2

147.

y = 4

149.

m = −6

151.

a = 7

153.

a = −40

155.

p = 15

157.

z = 3.46

159.

w = 60

161.

x = 23

163.

y = 9

165.

x = 6

167.

y = 3

169.

n = −2

171.

p = −1

173.

x = 5

175.

v = 1

177.

m = 0.25

179.

t = −9

181.

b = 2

183.

m = 6

185.

k=32k=32

187.

r = 3

189.

y = −4

191.

n = 2

193.

x = 34

195.

s = 10

197.

x=12x=12

199.

30 feet

201.

8 nickels

203.

Answers will vary.

205.

Answers will vary.

207.

Answers will vary.

Section 8.4 Exercises

209.

x = −1

211.

y = −1

213.

a=34a=34

215.

x = 4

217.

m = 20

219.

x = −3

221.

w=94w=94

223.

x = 1

225.

b = 12

227.

x = 1

229.

p = −41

231.

x=52x=52

233.

y = 10

235.

j = 2

237.

x = 18

239.

x = 18

241.

x = 20

243.

n = 9

245.

d = 8

247.

q = 11

249.

d = 18

251.

Answers will vary.

253.

Answers will vary.

Review Exercises

255.

yes

257.

no

259.

12

261.

a=43a=43

263.

u = 17

265.

c=1211c=1211

267.

n = 44

269.

f=103f=103

271.

y = 4

273.

n = −8

275.

−6 + m = 25; m = 31

277.

s = 11 − 3; 8 years old

279.

c − 46.25 = 9.75; $56.00

281.

x = 9

283.

p = 21

285.

n = 108

287.

x = 48

289.

m = 4

291.

x = 15

293.

r = 3

295.

p = 5

297.

x = −22

299.

y = −13

301.

k = −5

303.

x = 6

305.

u = −7

307.

x = −2

309.

s = −22

311.

y = 12

313.

r = 38

315.

y = 26

317.

n = 2

319.

a=143a=143

321.

x = 5

323.

p = −20

Practice Test

325.
  1. yes
  2. no
327.

c = 16

329.

x = −5

331.

x = 9

333.

y = 4

335.

m = 6

337.

d = −32

339.

x = −2

341.

p=23p=23

343.

2x − 4 = 16; x = 10

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