Student Answer Appendix SA49
CHAPTER 8
Exercises 8.1, pp. 801–805
1. inconsistent 3. consistent; independent
5. Multiply the first equation by 6 and the second equation by 10.
7. 9. 11.
13. 15. yes 17. yes
19. 21.
23. 25. 27. second equation, y,
29. second equation, x, 31. second equation, x,
33. 35. 37. 39. 41.
43. 45. (2, 8); consistent/independent 47. ; inconsistent
49. consistent/dependent
51. (4, 1); consistent/independent 53. consistent/independent
55. consistent/independent 57. 59.
61. 1 mph 4 mph 63. 2318 adult tickets; 1482 child tickets
65. premium: $3.97, regular: $3.87 67. nursing student $6500; science
major $3500 69. 150 quarters, 75 dimes
71. a. 100 lawns/mo, b. $11,500/mo
73. a. 1.6 billion bu, 3 billion bu, yes; b. 2.7 billion bu, 2.25 billion bu,
yes; c. $6.65, 2.43 billion bu 75. a. 3 mph, b. 5 mph
77. a. 3.6 ft/sec, b. 4.4 ft/sec 79. 1776; 1865
81. Tahiti: 402 mi
2
, Tonga: 290 mi
2
83. consistent/independent
85. $6552 at 8.5%; $11,551 at 6% 87.
89. verified
Exercises 8.2, pp. 814–818
1. triple 3. equivalent; systems 5. 7. Answers will vary.
9. Answers will vary. 11. yes, no 13. (5, 7, 4) 15. (2, 4, 3)
17. (1, 1, 2) 19. (4, 0, 3) 21. (3, 4, 5) 23. (1, 6, 9)
25. no solution, inconsistent 27.
29. , other solutions possible
31. 33.
35.
37. (1, 1, 2) 39. 41.
43. 45. 47.
49. 51. 53.
55. Monet $1,900,000; Picasso $1,100,000; van Gogh $4,000,000
57. elephant, 650 days; rhino, 464 days; camel, 406 days
59. Albatross: 3.6 m, Condor: 3.0 m, Quetzalcoatlus: 12.0 m
61. 175 $5 gold pieces; 50 $10 gold pieces; 25 $20 gold pieces
63. ; verified 65.
67.
; 69.
Mid-Chapter Check, pp. 817–818
1. (1, 1) consistent 2. (5, 3) consistent 3. 20 oz 4. No
5. 6. (1, 2, 3) 7. (1, 2, 3) 8.
9. Morphy: 13, Mozart: 8, Pascal: 16 10. prelude: 2.75 min, storm: 2.5
min, sunrise: 2.5 min, finale: 3.25 min
1p, p 5, p 422R1 R2
x 1H6,
43
2
IH11, 5I
x
2
y
2
4x 6y 9 0A 1, B 1, C 2
3.464 unitsa
1
2
,
1
3
, 3b11, 2, 32
a
11
3
,
10
3
,
7
3
b118, 6, 1021p 5, p 2, p2
a2, 1,
1
3
be1x, y, z2
|
x
5
2
y 2z 3f
51x, y, z2
|
x 6y 12z 56
1p 9, p 4, p21p, 2p, p 12
a
5
3
p
2
3
, p 2, pb
1p, 2 p, 2 p2
z 5
472°, 832°, 248°, 608°
m
1
m
2
;
12, 1212,
5
2
21
1
2
,
4
3
2;
13, 42;
51x, y2
|
6x y 226;
16, 122
13, 4212, 321
11
2
, 2212, 3213, 12
1
5
2
,
7
4
2110, 12
14, 3213, 5214, 12
x
y
108642
10
8
6
4
2
2
4
6
8
10
4
6
8
10
2
(1.1, 4.6)
x
y
108642
10
8
6
4
2
2
4
6
8
10
4
6
8
10
2
(6, 3)
x 3y 3y x 2,
x 3y 3y x 2y
4
3
x 5y
7
4
x 6,
Reinforcing Basic Concepts, p. 818
Exercise 1. Premium: $4.17/gal, Regular: $4.07/gal
Exercise 2. Verified
Exercises 8.3, pp. 823–826
1. a. 3 or 4 not possible
b. 3 or 4 not possible
c.
d.
e. 3 or 4 solutions not possible
f.
x
y
x
y
x
y
x
y
x
y
x
y
x
y
x
y
x
y
x
y
x
y
x
y
x
y
x
y
x
y
x
y
x
y
x
y
e
15.3R 35.7P 211.14
P R 0.10
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