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1. |
Solve the system of equations by elimination.
2x + y - z = 3
x + y + z = 5
x - 2y + z = 2
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A. |
(1, 1, 2) |
B. |
(2, 2, 1) |
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C. |
(1, 2, 1) |
D. |
(2, 1, 2) |
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Hint |
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2. |
The equation 2x - y + 3z = 5 represents _____________ |
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A. |
none of these. |
B. |
a plane. |
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C. |
a circle. |
D. |
a line. |
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Hint |
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3. |
If you solve the following system of equations by substitution, which statement is true?
x = z
x - 2y + z = 6
2x + y - 2z = 1
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A. |
Neither method will work. |
B. |
Both methods will work. |
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C. |
You can substitute z for x into the second and third equations. |
D. |
You can substitute x for z into the second and third equations. |
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Hint |
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4. |
Solve the system of three equations by elimination: 5x + 2y - 3z = 10
2x - 2y + 4z = 6
x - y + 2z = 3
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A. |
infinite solutions |
B. |
(3, 4, 2) |
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C. |
no solution |
D. |
(2, -5, 3) |
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Hint |
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5. |
If you are solving this system of equations by elimination, which of the following is the best choice for the first step? 2x + 3y - z = 4
-x + y + 2z = 3
3x + y + z = 1 |
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A. |
neither method is correct. |
B. |
Method II |
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C. |
Method I |
D. |
both methods are correct |
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Hint |
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