Algebra practice question

Answer: 4

The left side is x + 3a + 8, which equals x + 20 for all x only when 3a + 8 = 20, so a = 4.

Common wrong answers

If you answered 12

12 is 3a, not a.

If you answered 28

28 adds 8 instead of subtracting.

If you answered -4

−4 subtracts 8 with the wrong sign.

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