Advanced Math practice question

Answer: 3

x² + 4x² = 5x² = 45 → x² = 9 → x = 3.

Common wrong answers

If you answered 6

6 is the longer leg, 2x.

If you answered 9

9 is x².

If you answered 15

15 comes from 3x² = 45, adding the coefficients as 1 + 2.

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