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Question
Solve the following quadratic equation :
x2 +8x + 15 = 0
Solution
Given, x2 + 8x + 15 = 0
On splitting the middle term
x2 + 5x + 3x + 15 = 0
⇒ x(x + 5) + 3(x + 5) = 0
⇒ (x + 3)(x + 5) = 0
⇒ (x + 3) = 0 or (x + 5) = 0
⇒ x = – 3 or x = – 5
∴ – 3 and – 5 are the roots of the given quadratic equation.
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