Advanced Math practice question

Answer: 12

(2x + 3y)² = 4x² + 2(2x)(3y) + 9y² = 4x² + 12xy + 9y². The xy coefficient is 12.

Common wrong answers

If you answered 4

4 is the coefficient of x².

If you answered 6

6 is (2)(3), forgetting to double the cross term.

If you answered 9

9 is the coefficient of y².

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