Advanced Math practice question

Answer: 4

x⁴ − 16x² = x²(x² − 16) = 0, so x = 0, 4, or −4. The smallest positive solution is 4.

Common wrong answers

If you answered 0

0 is a solution but not positive.

If you answered 2

2 uses x² = 4 instead of x² = 16.

If you answered 16

16 is x², not x.

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