Advanced Math practice question

Answer: 8

Bring everything to one side: (x − 2)[(x + 5) − (2x − 1)] = (x − 2)(6 − x) = 0. The solutions are x = 2 and x = 6, whose sum is 8.

Common wrong answers

If you answered 2

2 is one solution.

If you answered 6

6 is the only solution if you divide both sides by (x − 2), which loses x = 2.

If you answered 12

12 is the product of the solutions.

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