alleryWhich quadratic has roots whose sum is 7 and product is 12?
Ax^2 - 7x + 12 = 0
Bx^2 + 7x + 12 = 0 with same coefficients
Cx^2 - 7x - 12 = 0 with negative constant
Dx^2 + 7x - 12 = 0 with negative constant
Answer & Solution
Correct answer: A. x^2 - 7x + 12 = 0
1. For x^2 + px + q = 0, sum of roots = -p, product = q.
2. Sum = 7 means -p = 7, so p = -7.
3. Product = 12 means q = 12.
4. The equation is x^2 - 7x + 12 = 0.
_Source: Selina Concise Mathematics Class 10, Ch 5 Quadratic Equations (Mistral OCR'd PDF), section on root-coefficient relations_
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