- y
0 X
61a. The graph is V-Shaped with vertex at (0, 5) and
passing through (1, 6) and (-1, 6). b. y = |x| + 5
Lesson 10-6 pp. 645-651
Go t I t? 1.f; f; | 2a. 0.9848 b. 1 c. 0.9659
d. 0.1564 e. sin 45° = cos 45°; a 45°-45°-90° triangle is
an isosceles right triangle, so the legs have the same
length, and the sine and cosine are the same ratio. 3. 1.9
4.41.8° 5. about 130 ft
Lesso n Ch eck 1.4,3,42. f 3. 34. about 6.4 cm
- 73.7° 6. To find the sine of an angle, you find the ratio
of the length of the opposite leg to the length of the
hypotenuse. To find the cosine of an angle, you find the
ratio of the length of the adjacent leg to the length of the
hypotenuse. 7. The student should use the sin-1 key;
sin-1 (0.9) = 64.15806724.
Ex e r c i se s 9. ^ 1 1. ^ 1 3. ^ 1 5. ^ 17.0.1736 - 0.0872 21. 0.9397 23. 0.9455 25. 5.5 27. 19.2
- 66.0 31. 60° 33. 37° 35. about 47.7 ft 37. Divide
the length of the adjacent side by the cosine of the acute
angle. 39. 514.3 41. 78.4 43a. about 1,720,000 ft
b. about 326 mi 45. 550 ft 47a. sin A b. cos A c. tan A - F 51. The number line has a filled circle on 0.5 and
points to the left.
55.
- (x
yes 56. yes 57. no
-w.v« 3)(x + 4)
- (x + 2)(x + 4)
- (x + 3)(x — 5)
61 (x+3)(x+6)
Chapter Review pp. 653-656
- trigonometric ratios 2. extraneous solution 3. unlike
radicals 4. rationalize the denominator 5. conjugates - 6.5 7. 12.5 8. 6.1 9. 84 10. 17.5 11. 0.7 12. 6.6
13.2.4 14. yes 15. yes 16. no 17. yes 18. no 19. yes - no 21. no 22. yes 23. -42 V6 24. V3 25. fa
- ^ 27. -^ x 2Vx 28. 30t4V3 29. Answers
vary. Sample: V 32s, ^ j = , 8
may
2 ', they all have the s and
the factor 2 under the radical. 30. sVTO 31. 2 V 6
- 4
- 2 V3 33. 4 - 2 VTO 34. — ^ + 9
-2 + V 3 36. - 3- + 3V3 in. 37. 169 38. 9 39. 18
40.21 41.2 42. 1 43. 1.5 44.1 45 .56.5 cm 3
- 2 V3 33. 4 - 2 VTO 34. — ^ + 9
- xs= 0 47. x> -4
- y
X
O
- y
- O X
- sin A = cos A = tan A = j
- sin A = cos A = | , tan A = ^
- length of AC ~ 9.9, length of BC = 6.7
- length of AB ~ 10.2, length of BC ~ 6.3
- length of AB ~ 26.9, length of AC ~ 20.0
- length of AC ~ 24.5, length of BC ~ 5.2
15
2V5
Ch ap t er 11
Get Ready! p. 661
2— 30 2 3 - 3 — H 4 — 5 120 35 r 3 0 7 64 49 729
IS 8-5x° -7,9 10. 11. -13 12. 0, 3
- -f, 5 14. -5, - § 15. -10, -1 16. -3, 7
- -j, | 18. no solution 19.1 20.4 21. The excluded
cr>
Q_
a>n
ro
o_
§
I
a
C
Po w erAlg eb ra.com Selected Answers 911