Algebra practice question

Answer: 6

Substitute the point: 2c − 3(c − 4) = c, so −c + 12 = c and c = 6.

Common wrong answers

If you answered 3

Check the distribution: 2c − 3c + 12 = c leads to c = 6.

If you answered 4

4 comes from dropping a term; carefully distribute −3 over (c − 4) to get −3c + 12.

If you answered 12

12 is the constant after distributing; the equation −c + 12 = c still must be solved, giving 6.

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