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Question
If the sum of the roots of the quadratic equation x2 + kx + 6 = 0 is 6, then the value of k is ______.
Options
– 12
6
12
– 6
Solution
If the sum of the roots of the quadratic equation x2 + kx + 6 = 0 is 6, then the value of k is – 6.
Explanation:
Given the quadratic equation, x2 + kx + 6 = 0
We know, Sum of roots (α + β) = `- b/a`
6 = `- k/1`
– k = 6
k = – 6
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