Algebra practice question

Answer: 6

6x + 6 − 2x = 30 gives 4x = 24, so x = 6.

Common wrong answers

If you answered 3

3 treats 6(x + 1) as 6x + 1.

If you answered 4

4 uses 6x − 2x = 24 with the 6 added instead of subtracted.

If you answered 9

9 subtracts 2x from the wrong side.

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