Advanced Math practice question

Answer: 1

Squaring gives 2x + 7 = x² + 4x + 4, so x² + 2x − 3 = 0 and x = 1 or x = −3. Only x = 1 checks: √9 = 3. At x = −3, √1 = 1 but x + 2 = −1.

Common wrong answers

If you answered 3

3 gives √13 on the left and 5 on the right.

If you answered -3

−3 is the extraneous root; the right side would be −1.

If you answered -1

−1 gives √5 on the left and 1 on the right.

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