Algebra practice question

Answer: 3

Substitute: 2k + 6 = 12, so 2k = 6 and k = 3.

Common wrong answers

If you answered 6

6 is 2k, not k.

If you answered 9

9 comes from 2k − 6 = 12 (wrong sign on the y term: −3 × −2 = +6).

If you answered -3

−3 has the wrong sign.

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