Advanced Math practice question

Answer: -9 or −9

Take square roots: x + 2 = 7 or x + 2 = −7. So x = 5 or x = −9. The negative solution is −9.

Common wrong answers

If you answered 5

5 is the positive solution; the question asks for the negative one.

If you answered -5

−5 comes from x + 2 = −7 solved as x = −5 (dropping the 2 wrongly); −7 − 2 = −9.

If you answered -51

−51 is 49 − 2 with a sign slip, from dropping the square. Take the square root first.

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