Advanced Math practice question

Answer: 20

x² + y² = (x + y)² − 2xy = 36 − 16 = 20. (The numbers are 2 and 4.)

Common wrong answers

If you answered 28

28 subtracts xy once instead of twice.

If you answered 36

36 is (x + y)², forgetting to subtract 2xy.

If you answered 52

52 adds 2xy instead of subtracting.

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