Answer:
–y – 2x = 6 . . . choice 1
Step-by-step explanation:
Consider the system obtained using the other answer choices:
-y +2x = 12 . . . choice 2
The result of multiplying the given equation by -1/2 is ...
-y +2x = -6 . . . . a line parallel to that of answer choice 2. The system would have no solution
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y = 2x +6 . . . choice 3
Solve the given equation for y by adding 4x and dividing by 2. That will give ...
y = 2x +6 . . . . a line identical to that of answer choice 3. The system would have an infinite number of solutions.
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y = 2x +12 . . . choice 4
As we found in the previous discussion, the given line can be written as ...
y = 2x + 6 . . . . a line parallel to that of answer choice 4. The system would have no solution.
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The attached graph shows the given line and that of answer choice 1.
