Advanced Math practice question

Answer: 6

x² + x − 42 = 0 → (x + 7)(x − 6) = 0 → x = 6 (positive).

Common wrong answers

If you answered 7

7 gives 7 + 49 = 56, not 42.

If you answered 21

21 is half of 42, treating the sum as 2x.

If you answered -7

−7 is the rejected negative root.

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