Algebra & Equations · Question 24 · Medium
Which quadratic equation has roots 3 and −5?
- x² + 2x + 15 = 0
- x² + 2x − 15 = 0
- x² − 2x − 15 = 0
- x² − 8x + 15 = 0
Answer and explanation
Answer: B. x² + 2x − 15 = 0
Explanation: x² − (sum of roots)x + (product of roots) = 0. Sum = −2, product = −15, so x² + 2x − 15 = 0.
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