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Test 1, on quizzes 1 to 5, is on Wednesday, July 5.
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answers: c c b b a a a c b (written answers are below)
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3.2
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1. Write equations for this problem. The difference of two numbers is 7. If
one number is added to three times the the other, the result is -1
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a
x - y = -1
3x - y = 7
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b
x + y = 7
x - 3y = -1
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c
x - y = 7
3x + y = -1
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d nota
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2. In the previous problem, the solution for x is
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a 1/2
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b 1
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c 3/2
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d nota
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3. The cost and revenue functions for producing and selling x units
of a CD are given by
C(x) = 15,000 + 12x and R(x) = 32x, respectively. If the
company breaks even, then what is
R(x)?
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| a 750
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b 24,000 |
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c 7,500 |
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d nota |
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3.3 |
4.
Is ( 2,-1,3) a solution to this system?
x + y + z = 4
x - 2y - z = 1
2x - y - z = 1 |
| a yes |
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b no |
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c nota |
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3.3
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| 5.
For the system:
x - y + z = 4 (A)
x + 2y - z = -1 (B)
x + y - 3z = -2 (C)
If you want to eliminate x, then you should |
| a Subtract (B) from (A) and subtract
(C) from (A) |
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b Add (B) and (A) and subtract (C) from (A) |
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c Subtract
(B) from (A) and add (C) and (A) |
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d nota |
| 4.1
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| 6. Solve: 10x + 6 > -14
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| a x
> -2 |
| b x
< 2 |
| c x
< -2 |
| d nota |
7. Solve: -66(2 - b) > 24(2b + 2)
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a b >
10 |
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b b <
10 |
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c b <
-10 |
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d nota |
| 4.2 |
| 8. Solve: 1 < ½ x - 4
< 7 |
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a 5 < x < 11 |
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b no solution |
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c 10 < x
< 22 |
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d nota |
| 4.3 |
| 9. Solve |x - 2| = 0 |
a no
solution
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b 2
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c -2
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d nota
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| written problems |
| 10. Solve |4x + 1| = 11
answer: -3, 5/2 |
| 11. Solve |2x + 2| < 14
answer: -8 < x < 6 |
| 12. |2x + 1| > 15
answer: x < -8 or 7 < x |
| 13. EC Solve |3x + 2| + 7 =
23 answer: -6, 14/3 |
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14. Take home ICQ7- 3- 06 due Monday: Using your choice in problem 5, solve
for y and z. Show all work. |
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