Advanced Math practice question

Answer: 5

With width w, w² = 4w + 5, so w² − 4w − 5 = (w − 5)(w + 1) = 0 and w = 5.

Common wrong answers

If you answered 4

4 copies the coefficient.

If you answered 25

25 is the area.

If you answered -1

−1 is the other root, not a length.

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