Algebra practice question

Answer: -28

f(2) = −8 + 20 = 12. Then f(12) = −48 + 20 = −28.

Common wrong answers

If you answered 12

12 is f(2), the inner value only.

If you answered 28

28 has the wrong sign.

If you answered -68

−68 comes from f(f(2)) computed as −4(12) − 20, subtracting the 20 instead of adding it.

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