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1. |
If you solve the following system of equations by elimination, which of the following is the best choice for the first step?
2x + y - z = 3
x + y + z = 5
x - 2y + z = 2
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A. |
Both methods will work. |
B. |
Neither method will work. |
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C. |
Subtract the second and third equation to eliminate the z variable. |
D. |
Add the first and second equations to eliminate the z variable. |
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Hint |
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2. |
Three planes can |
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A. |
intersect at one point. |
B. |
have no points in common. |
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C. |
All of the choices are true. |
D. |
intersect in a line. |
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Hint |
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3. |
Solve the system of 3 equations by substitution. x = 3y + 2z
2x + 3y + 2z = 3
-x + y - z = 6 |
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A. |
(8, 4, -2) |
B. |
infinite solutions |
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C. |
no solution |
D. |
(1, 3, -4) |
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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. |
(2, -5, 3) |
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C. |
(3, 4, 2) |
D. |
no solution |
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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 I |
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C. |
Method II |
D. |
both methods are correct |
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Hint |
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