Use a calculator to decide whether the statement is true or false.cos (2 ? 90°) = cos2 90° - sin2 90°
A. True
B. False
Answer: A
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Solve the problem.Assume that the sales of a certain appliance dealer are approximated by a linear function. Suppose that sales were $14,000 in 1982 and $68,000 in 1987. Let 
represent 1982. Find the equation giving yearly sales 
.
A. S(x) = 10,800x + 68,000 B. S(x) = 10,800x + 14,000 C. S(x) = 54,000x + 14,000 D. S(x) = 54,000x + 68,000
Find the vertex, the focus, and the directrix of the parabola.3x2 - 30x - y + 77 = 0
A. Vertex: 
; Focus: 
; Directrix: y = 
B. Vertex: 
; Focus: 
; Directrix: x = 
C. Vertex: 
; Focus: (5, 14); Directrix: x = 10
D. Vertex: 
; Focus: (5, 5); Directrix: x = -1
Solve the problem.A life insurance company uses the following rate table for annual premiums for women for term life insurance. Use a graphing utility to fit an exponential function to the data. Predict the annual premium for a woman aged 70 years.
A. y = 8.94e0.068x, $1044 B. y = -9306.4 + 2516.3 ln (x), $1723 C. y = 0.0000398x4.06, $1233 D. y = 6.367e0.068x, $743
Determine the quadratic function whose graph is given.
Vertex: (1, 4)y-intercept: (0, 3)
A. f(x) = -x2 - 4x + 3 B. f(x) = -x2 + 2x + 3 C. f(x) = -x2 + 2x - 3 D. f(x) = x2 - 4x + 3