Advanced Math practice question

Answer: 3

Multiply both sides by (x − 2): x = 3(x − 2) = 3x − 6. Then −2x = −6, so x = 3. Check: 3/(3 − 2) = 3.

Common wrong answers

If you answered 1

1 would come from x = 3x − 2, forgetting to distribute the 3 onto the −2.

If you answered 6

6 is 3 × 2, from 3(x − 2) = 3x − 6 with the x terms dropped. Collect them: x − 3x = −6.

If you answered -3

−3 has a sign slip: from −2x = −6, dividing by −2 gives x = 3, not −3.

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