Algebra practice question

Answer: 1/2 or .5 or 0.5

The first line has slope −a/2, which must be −1/4, the negative reciprocal of 4. So a = 1/2.

Common wrong answers

If you answered 8

8 uses slope 4 with the sign wrong.

If you answered -8

−8 makes the slopes equal, giving parallel lines.

If you answered -1/2

−1/2 has the sign wrong.

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