Advanced Math practice question

Answer: 3

Subtract x² from both sides — the squared terms cancel — leaving 4x = 12, so x = 3.

Common wrong answers

If you answered 8

8 is 12 − 4, subtracting the coefficient instead of dividing by it.

If you answered 9

9 is 3², perhaps from squaring the answer. The equation reduces to 4x = 12.

If you answered 48

48 is 4 × 12, multiplying instead of dividing. 4x = 12 gives x = 3.

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