Algebra practice question

Answer: -1/2 or -.5 or -0.5

Perpendicular slopes multiply to −1, so 2k = −1 and k = −1/2.

Common wrong answers

If you answered 2

2 would make the lines parallel.

If you answered 1/2

1/2 has the sign wrong.

If you answered -2

−2 changes the sign but does not invert.

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