Advanced Math practice question

Answer: 2

x³ − 4x = 0 → x(x² − 4) = 0 → x = 0, 2, or −2. The positive solution is 2.

Common wrong answers

If you answered 0

0 is a solution, but not positive.

If you answered 4

4 comes from dividing both sides by x² instead of x.

If you answered -2

−2 is a solution, but not positive.

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