Advanced Math practice question

Answer: -10 or −10

x² = 100 has two solutions, 10 and −10. The condition x < 0 picks the negative one: x = −10.

Common wrong answers

If you answered 10

10 squares to 100, but the question says x is negative.

If you answered -50

−50 halves 100 instead of taking its square root; (−50)² = 2,500.

If you answered -100

(−100)² = 10,000, not 100. The square root of 100 is 10.

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