Advanced Math practice question

Answer: 10

f(x) = a·x(x − 4); f(2) = a(2)(−2) = −4a = −8 gives a = 2, so f(5) = 2(5)(1) = 10.

Common wrong answers

If you answered 5

5 uses a = 1.

If you answered 20

20 uses f(5) = 2(5)(2).

If you answered -10

−10 has the sign wrong; f(5) is above the axis.

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