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Question
Find the roots of the following quadratic equation by factorisation:
x2 – 3x – 10 = 0
Solution
x2 – 3x – 10
= x2 - 5x + 2x - 10
= x(x - 5) + 2(x - 5)
= (x - 5)(x + 2)
Roots of this equation are the values for which (x - 5)(x + 2) = 0
⇒ x = 5 or x = -2
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