Algebra practice question

Answer: 8

Slope: (0 − 12)/(6 − 0) = −2. So f(x) = −2x + 12, and f(2) = −4 + 12 = 8.

Common wrong answers

If you answered 4

4 is f(4), or 12 − 2 × 4. At x = 2 the drop from 12 is only 2 × 2 = 4, leaving 8.

If you answered 6

6 is halfway between 12 and 0, which would be f(3), not f(2).

If you answered 10

10 is 12 − 2, dropping the slope once instead of twice.

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