Advanced MathEasyPositive solution of a simple quadratic
Advanced Math practice question
What is the positive solution of the equation x² − 9 = 0?
Answer: 3
x² = 9, so x = 3 or x = −3; the positive one is 3.
Common wrong answers
- If you answered 9
- 9 is x², not x.
- If you answered -3
- −3 is the negative solution.
- If you answered 4.5
- 4.5 halves 9 instead of taking the square root.
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