12.4.8: Chapter 8

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May 28, 2023
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- 12.4.7: Chapter 7
- 12.4.9: Chapter 9

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Be Prepared

8.1

$28$

8.2

$x - 5$

8.3

yes

8.4

$1$

8.5

$- \frac{8}{3}$

8.6

$- 25$

8.7

$4 y$

8.8

$4$

8.9

$- 21$

8.10

$3$

8.11

$12$

8.12

$478$

Try It

8.1

8.2

8.3

x = −16

8.4

x = −20

8.5

n = −1

8.6

x = −4

8.7

$p = \frac{7}{6}$

8.8

$q = \frac{2}{3}$

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

$x = - \frac{4}{7}$

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

$j = \frac{5}{3}$

8.66

$k = \frac{5}{2}$

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

$x = \frac{1}{2}$

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

yes

x = 5

$b = \frac{1}{2}$

p = −11.7

11.

a = 10

13.

$x = \frac{7}{3}$

15.

y = 13.8

17.

x = −27

19.

$q = - \frac{1}{4}$

21.

$y = \frac{27}{20}$

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.

$f - \frac{1}{3} = \frac{1}{12}; f = \frac{5}{12}$

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.

$d = \frac{13}{24}$

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.

$q = \frac{5}{2}$

95.

y = −1

97.

m = −5

99.

$t = \frac{5}{2}$

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.

$x = - \frac{3}{4}$

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.

$k = \frac{3}{2}$

187.

r = 3

189.

y = −4

191.

n = 2

193.

x = 34

195.

s = 10

197.

$x = \frac{1}{2}$

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.

$a = \frac{3}{4}$

215.

x = 4

217.

m = 20

219.

x = −3

221.

$w = \frac{9}{4}$

223.

x = 1

225.

b = 12

227.

x = 1

229.

p = −41

231.

$x = - \frac{5}{2}$

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.

259.

261.

$a = \frac{4}{3}$

263.

u = 17

265.

$c = \frac{12}{11}$

267.

n = 44

269.

$f = \frac{10}{3}$

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.

$a = \frac{14}{3}$

321.

x = 5

323.

p = −20

Practice Test

325.

ⓐ yes
ⓑ no

327.

c = 16

329.

x = −5

331.

x = 9

333.

y = 4

335.

m = 6

337.

d = −32

339.

x = −2

341.

$p = \frac{2}{3}$

343.

2x − 4 = 16; x = 10

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Be Prepared

Try It

Section 8.1 Exercises

Section 8.2 Exercises

Section 8.3 Exercises

Section 8.4 Exercises

Review Exercises

Practice Test

Be Prepared

Try It

Section 8.1 Exercises

Section 8.2 Exercises

Section 8.3 Exercises

Section 8.4 Exercises

Review Exercises

Practice Test

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