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Question
If the roots of the quadratic equation x2 + 12x + a = 0 are real and equal, then find the value of a.
Solution
Equation given is, x2 + 12x + a = 0
As a result of the quadratic equation's real and equal roots,
∴ Discriminant, D = 0
⇒ B2 – 4AC = 0
⇒ (12)2 – 4 × 1 × a = 0
⇒ 4a = 144
⇒ a = 36
As a result, a has a value of 36.
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