Practice and Applications

7. $A = 4 π t^{2}$ $A = 4 π t^{2}$
9. $y = 50.000 - 1.25 x$ $y = 50.000 - 1.25 x$
11. 16, $- 47$ $- 47$
13. 3, $\sqrt{1 - 4 h} + 2$ $\sqrt{1 - 4 h} + 2$
15. $h^{3} + 11 h^{2} + 36 h$ $h^{3} + 11 h^{2} + 36 h$
17. $- 4$ $- 4$
19. $- 3.67,$ $- 3.67,$ 16.7
21. 0.16503, $- 0.21476$ $- 0.21476$
23. Domain: all real numbers; range: all real numbers $f (x) \geq 1$ $f (x) \geq 1$
25. Domain: all real numbers $t > - 4;$ $t > - 4;$ range: all real numbers $g (t) > 0$ $g (t) > 0$
27. Domain: all real numbers except 5; range: all real numbers $f (n) > 1$ $f (n) > 1$
29.
31.
33.
35.
37.
39. 0.4
41. 0.2, 5.8
43. 1.4
45. $- 4.1,$ $- 4.1,$ 1.0
47. All real numbers $y \geq - 6.25$ $y \geq - 6.25$
49. All real numbers $y \leq - 2.83$ $y \leq - 2.83$ or $y \geq 2.83$ $y \geq 2.83$
51. Either a or b is positive, the other is negative.
53. $(1, \sqrt{3})$ $(1, \sqrt{3})$ or $(1, - \sqrt{3})$ $(1, - \sqrt{3})$
55. In any quadrant (not on an axis)
57. Many possibilities (two shown)
59. $y = \sqrt{x + 1} + 1$ $y = \sqrt{x + 1} + 1$
61. They are reflections of each other across the y-axis.
63. Yes; no two x-values arc the same.
65. $A = \frac{1}{2} π s^{2}$ $A = \frac{1}{2} π s^{2}$
67. 13.4
69. $72.0 °$ $72.0 °$
71.
73.
75. $L = 2 π r + 12$ $L = 2 π r + 12$
77. f(T)
79.
81.
83.
85. 11.3 ft
87. 3.5 h
89. $33 ° C$ $33 ° C$
91. 1.03 ft
93. 15.5 ft
95. 6.5 h