If the roots of the quadratic equation are in the ratio , what is the positive value of ?
Answer and explanation
Correct answer: A. 8
- Step 1: Let the roots be and .
- Step 2: Product of roots: (for positive ).
- Step 3: Sum of roots: .
- Step 4: From Vieta's formulas, sum of roots is , so .
Answer
8.
Why not the others: '6' assumes roots 2 and 4 (product 8); '7' assumes roots 3 and 4 (sum 7); '9' is an arithmetic error.
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