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Find the roots of the following quadratic equations by factorisation:

x^{2} – 3x – 10 = 0

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#### Solution

x^{2} – 3x – 10

= x^{2} - 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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