Advanced Math practice question

Answer: 2

Cross-multiply: x · x = 4, so x² = 4 and x = 2 (positive). Check: 1/2 = 2/4.

Common wrong answers

If you answered 4

4 gives 1/4 on the left and 1 on the right — not equal.

If you answered -2

−2 also satisfies x² = 4, but the question requires x > 0.

If you answered 0.25

0.25 is 1/4, one side of the equation evaluated with x = 1, not a solution.

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