Question

Find the roots of the following quadratic equation by factorisation:

x² – 3x – 10 = 0

Answer 1

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 = 0 or x + 2 = 0

⇒ x = 5 or x = -2