Advanced Math practice question

Answer: 4

w(w + 6) = 40 gives w² + 6w − 40 = (w + 10)(w − 4) = 0, so w = 4.

Common wrong answers

If you answered 10

10 is the length (4 + 6), or the size of the rejected root.

If you answered -10

−10 is the negative root, impossible for a width.

If you answered 6.67

6.67 is 40/6, dividing area by the 6 instead of solving.

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