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If alpha and beta are roots of x^2 - 7x + 10 = 0, then alpha + beta + alpha*beta equals
A7
B17
C10
D3
Answer & Solution
Correct answer: B. 17
1. For x^2 - 7x + 10 = 0, sum of roots = 7 and product = 10.
2. alpha + beta = 7 and alpha * beta = 10.
3. Required value = 7 + 10.
4. So the answer is 17.
_Source: Selina Concise Mathematics Class 10, Ch 5 Quadratic Equations (Mistral OCR'd PDF), section on relations_
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