Question

Solve the following equation by factorization:

15x² – 28 = x

Answer 1

Given,

⇒ 15x² – 28 = x

⇒ 15x² – x – 28 = 0

⇒ 15x² – 21x + 20x – 28 = 0

⇒ 3x(5x – 7) + 4(5x – 7) = 0

⇒ (5x – 7)(3x + 4) = 0

⇒ (5x – 7) = 0 or (3x + 4) = 0   ...[Using zero-product rule]

⇒ 5x = 7 or 3x = – 4

⇒ `x = 7/5` or `x = (-4)/3`

Hence, `x = {(-4)/3, 7/5}`.