Algebra practice question

Answer: -3

Perpendicular to slope 1/2 means slope −2, so f(x) = −2x + 5 and f(4) = −3.

Common wrong answers

If you answered 3

3 assumes f is constant.

If you answered 4.5

4.5 uses the slope 1/2 instead of −2.

If you answered -8

−8 forgets the intercept 5.

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