Advanced Math practice question

Answer: 10

(x + y)² = x² + 2xy + y² → 49 = 29 + 2xy → xy = 10.

Common wrong answers

If you answered 20

20 is 2xy, before halving.

If you answered 22

22 is 29 − 7, subtracting the sum instead of squaring it.

If you answered -10

−10 has the wrong sign.

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