Advanced Math practice question

Answer: 4

Let s = √x: s² + 3s − 10 = 0 → (s + 5)(s − 2) = 0 → s = 2 (positive), so x = 4.

Common wrong answers

If you answered 2

2 is √x, not the number.

If you answered 7

7 comes from x + 3 = 10, treating the square root as 1.

If you answered 25

25 comes from s = −5, which is not a square root.

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