Advanced MathHardPositive root of a quadratic with fractional solution
Advanced Math practice question
If 4x² + 4x − 3 = 0 and x > 0, what is the value of x?
Answer: 1/2 or 0.5
4x² + 4x − 3 = (2x − 1)(2x + 3), so the positive root is 1/2.
Common wrong answers
- If you answered 1
- 1 gives 4 + 4 − 3 = 5.
- If you answered -3/2
- −3/2 is the negative root.
- If you answered 3/4
- 3/4 is the value of x² + x, not x.
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