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Question
Find the roots of the following quadratic equation by factorisation:
2x2 + x – 6 = 0
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Solution
2x2 + x – 6
= 2x2 + 4x - 3x - 6
= 2x(x + 2) - 3(x + 2)
= (x + 2)(2x - 3)
Roots of this equation are the values for which (x + 2)(2x - 3) = 0
⇒ x = -2 or x = `3/2`
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