Advanced Math practice question

Answer: 8

Multiply both sides by (x − 4): 12 = 3(x − 4) = 3x − 12, so 3x = 24 and x = 8.

Common wrong answers

If you answered 0

0 comes from 12 = 3x − 12 solved as 3x = 0 (a sign slip); 12 + 12 = 24.

If you answered 4

4 is excluded — it makes the denominator zero.

If you answered 7

7 comes from 12 ÷ 4 = 3 then 3 + 4, which misreads the equation.

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