# statistscs

This is an open-book exam. You may refer to your text and other course

materials as you work on the exam, and you may use a calculator. You

must complete the exam individually. Neither collaboration nor

consultation with others is allowed.

Record your answers and work on the separate answer sheet provided.

There

are 30 problems. Problems #1–12 are Multiple Choice. Problems #13–21

are Short Answer. (Work not required to be shown) Problems #22–30 are

Short Answer with work required to be shown.

MULTIPLE CHOICE

1. Determine the domain and range of the piecewise function. 1. ______

A. Domain [–3, 3]; Range [–4, 2] B. Domain [–4, 2]; Range [–3, 3] C.

Domain [–4, 2]; Range [–2, 1] D. Domain [–2, 1]; Range [–4, 2]

2. Solve: 11 2 2 xx + = − 2. ______

A. No solution B. −13 C. 7 D. −1, 7

2 4 4 -2
-4
2
4
-2
College Algebra MATH 107 Fall, 2018, V4.5
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3. Determine the interval(s) on which the function is decreasing. 3. ______

A. ( ) , 2.5− − and ( ) 1,4.5

B. ( ) ,1− − and ( ) 3,

C. ( ) 1, 3−

D. ( ) 1.3, 1.3−

4. Determine whether the graph of 5yx =+ is symmetric with respect to the origin, the x-axis, or the y-axis. 4. ______

A. not symmetric with respect to the x-axis, not symmetric with respect

to the y-axis, and not symmetric with respect to the origin B.

symmetric with respect to the x-axis only C. symmetric with respect to

the y-axis only D. symmetric with respect to the origin only

5. Solve, and express the answer in interval notation: | 9 – 4x |  23. 5. ______

A. (–, 8]  [–7/2, )

B. [–7/2, 8]

C. (–, –7/2]  [8, )

D. (–,–7/2]

College Algebra MATH 107 Fall, 2018, V4.5
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6. Which of the following represents the graph of 4x + 7y = 28 ? 6. ______

A. B.

C. D.

College Algebra MATH 107 Fall, 2018, V4.5
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7.

Write a slope-intercept equation for a line parallel to the line x + 5y

= 8 which passes through the point (10, –6). 7. ______

A.
1
8
5 yx =−

B.
1
6
5 yx =− −

C.
1
4
5 yx =− −

D. 5 44 yx =− +

8. Does the graph below represent a function and is it one-to-one? 8. ______

A.

It is a function and it is one-to-one. B. It is a function but not

one-to-one. C. It is not a function but it is one-to-one. D. It is not a

function and it is not one-to-one.

College Algebra MATH 107 Fall, 2018, V4.5
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9. Express as a single logarithm: log x – 3 log y + log 1 9. ______
A. ( ) log 3 1 xy −+

B.
3
1
log
x
y  +  

C. log
31 x y   + 

D. 3 log x y   

10. Which of the functions corresponds to the graph? 10. ______

A. ( ) 2 xf x e − =+
B. ( ) 3 xf x e =− + C. ( ) 3 xf x e=+
D. ( ) 3 xf x e − =+

College Algebra MATH 107 Fall, 2018, V4.5
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11. Suppose that for a function f , f has no x-intercepts.

Which of the following statements MUST be true? 11. ______ A. f (x)

> 0 for all x in the domain of f. B. f is an invertible function. C.

The equation f (0) = y has no real-number solutions. D. The equation f

(x) = 0 has no real-number solutions.

12.

The graph of y = f (x) is shown at the left and the graph of y = g(x)

is shown at the right. (No formulas are given.) What is the relationship

between g(x) and f (x)? 12. ______

y = f (x) y = g(x)

A. g(x) = f (x + 5) – 2 B. g(x) = f (x – 2) – 5 C. g(x) = f (x – 5) – 2 D. g(x) = f (x + 2) – 5

2 4 2 4 -2
-4
2
4
2 4 2 4 -2
-4
2
4
College Algebra MATH 107 Fall, 2018, V4.5
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SHORT

ANSWER: 13. Multiply and simplify: (5 − 2i)(7 + 3i). Write the answer

in the form a + bi, where a and b are real numbers. Answer: ________

14. Solve, and write the answer in interval notation: 5 0 2 x x +  − . Answer: ________

15.

A bowl of soup at 175 F. is placed in a room of constant temperature

of 70 F. The temperature T of the soup t minutes after it is placed in

the room is given by

T(t) = 70 + 105 e – 0.075 t

Find the temperature of the soup 18 minutes after it is placed in the room. (Round to the nearest degree.) Answer: ________

16. Find the value of the logarithm: 4
1
log
16    . Answer: ________

17. Solve: 4539 x− = . Answer: ________

18.

Suppose \$6,000 is invested in an account at an annual interest rate of

5.2% compounded continuously. How long (to the nearest tenth of a year)

will it take the investment to double in size? Answer: ________

19. Let f (x) = x2 + 10x + 27.

(a) Find the vertex. Answer: ________

(b) State the range of the function. Answer: ________

(c) On what interval is the function decreasing? Answer: ________

College Algebra MATH 107 Fall, 2018, V4.5
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20. Consider the polynomial P(x), shown in both standard form and factored form.
4

3 2 1 1 7 41 1 ( ) 3 ( 3)( 1)( 2)( 5) 10 2 10 10 10 P x x x x x x x x x

= − − + − = + − − − (a) Which sketch illustrates the end behavior of

the polynomial function?

(b) State the zeros of the function. Answer: ________________

(c) State the y-intercept. Answer: ________________

(d) State which graph below is the graph of P(x). Answer: ________

GRAPH A GRAPH B

GRAPH C GRAPH D

A.

B. C. D.
vvvv
vvvv

vvvv vvvv

College Algebra MATH 107 Fall, 2018, V4.5
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21. Let
39
()
2
x
fx
x

=

.

(a) State the domain. Answer: _________________

(b) State the horizontal asymptote. Answer: _________________

(c) State the vertical asymptote(s). Answer: _________________

(d) Which of the following represents the graph of
39
()
2
x
fx
x

=

GRAPH A. GRAPH B.

GRAPH C. GRAPH D.

College Algebra MATH 107 Fall, 2018, V4.5
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SHORT ANSWER, with work required to be shown, as indicated.

22. Let x xf − = 5)( and g(x) = x + 2.

(a) Find ) 4( −        g f
. Show work.
(b) Find the domain of the quotient function
g f
. Explain.

23. Points (–8, 1) and (–2, 7) are endpoints of the diameter of a circle.

(a)

What is the length of the diameter? Give the exact answer, simplified

as much as possible. Show work. (b) What is the center point C of the

circle? (c) Given the point C you found in part (b), state the point

symmetric to C about the y-axis.

24. Find the

equation for a line which passes through the points (6, 3) and (4, –5).

Write the equation in slope-intercept form. Show work.

25.

Rita, a resident of Metropolis, pays Metropolis an annual tax of \$70

plus 1.7% of her annual income. If Rita paid \$1,056 in tax, what was

Rita’s income? Show work.

26. Let f (x) = 5×2 + 7 and g(x) = x – 1.

(a) Find the composite function ) )(( x gf  and simplify. Show work. (b) Find ( )( 3) fg− o . Show work.

27. Find the exact solutions and simplify as much as possible: 5×2 = 1 + 2x. Show work.

28. Given the function
1
( ) 7
4 f x x =− , find a formula for the inverse function. Show work.

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29. Donut Delights, Inc. has determined that when x donuts are made daily, the profit P, in dollars, is given by

P(x) = –0.002 x2 + 3.2x – 820

(a) What is the company’s profit if 600 donuts are made daily?

(b) How many donuts should be made daily in order to maximize the company’s profit? Show work.

30. Solve: 2 11 56
0
7 49
x x x + += + − . Show work