Advanced Math practice question

Answer: 4

(x + y)² − (x − y)² = (x² + 2xy + y²) − (x² − 2xy + y²) = 4xy.

Common wrong answers

If you answered 0

0 assumes the two squares are equal.

If you answered 2

2 counts only one of the 2xy terms.

If you answered -4

−4 subtracts in the wrong order.

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