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1. |
Solve the system 3x + 2y – z = –1, –2x + –3y + 2z = 5, 4x – y + 3z = 11. |
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A. |
(1, –1, 2) |
B. |
(2, –1, 2) |
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C. |
(1, 4, –3) |
D. |
(2, 4, –2) |
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Hint |
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2. |
Vince and Brian each need two kinds of items at the store. Vince bought 10 of item A and 14 of item B, and spent $97. Brian bought 8 of item A and 25 of item B, and spent $119. How much did each item cost? |
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A. |
item A = $2.10
item B = $1.14 |
B. |
item A = $3
item B = $5.50 |
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C. |
item A = $5.50
item B = $3 |
D. |
item A = $1.14
item B = $2.10 |
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Hint |
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3. |
Solve 2.4x + 1.7y = 8.2, 3.8x – 0.8y = 5.3. Round to the nearest hundredth. |
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A. |
(1.86, –2.20) |
B. |
(–1.86, –2.20) |
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C. |
(–1.86, 2.20) |
D. |
(1.86, 2.20) |
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Hint |
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4. |
Two sides of an angle are contained in lines whose equations are 6x + 4y = 15 and 7x – 9y = 3. Find the coordinates of the vertex of the angle. Round to the nearest hundredth. |
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A. |
(–1.79, 1.06) |
B. |
(–147, –87) |
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C. |
(1.79, 1.06) |
D. |
(147, 87) |
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Hint |
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5. |
Which method of finding solutions would work best to find the solutions to the system 12.4x – 3.66y = 12.19, 3.9x + 6.17y = 19.28, and why? |
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A. |
Cramer's Rule, because there are fewer calculations. |
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B. |
elimination, because Cramer's Rule doesn't apply to this problem |
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C. |
elimination, because 6.17 is a factor of 3.66 |
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D. |
Cramer's Rule, because none of the other methods will correctly solve the problem |
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Hint |
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