Advanced Math practice question

Answer: 4

Square both sides: 3x + 4 = x², so x² − 3x − 4 = 0, giving (x − 4)(x + 1) = 0. x = −1 fails the original equation (a square root can't be negative), so x = 4. Check: √16 = 4.

Common wrong answers

If you answered 2

2 gives √10 ≈ 3.16, not 2.

If you answered 16

16 is 3x + 4 at the solution — the value under the root, not x.

If you answered -1

−1 appears after squaring but doesn't satisfy the original: √1 = 1, not −1.

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