Advanced Math practice question

Answer: 16

(x + 3)² = x² + 6x + 9 and (x − 1)(x + 1) = x² − 1. Subtract: 6x + 10, so a = 6, b = 10, and a + b = 16.

Common wrong answers

If you answered 6

6 is a alone.

If you answered 10

10 is b alone.

If you answered 14

14 comes from x² + 6x + 9 − x² + 1 miscounted as 6x + 8 (subtracting the 1 instead of adding it).

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