Advanced Math practice question

Answer: 16

(x² + 8x + 16) − (x² − 8x + 16) = 16x, so k = 16.

Common wrong answers

If you answered 0

0 forgets that the middle terms have opposite signs.

If you answered 8

8 is one of the two middle coefficients.

If you answered 32

32 adds the constants instead of cancelling them.

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