Question

Factorise the following:

16a² – 9b² + 30bc – 25c²

Answer 1

Given: 16a² – 9b² + 30bc – 25c²

⇒ 16a² – (9b² – 30bc + 25c²)

⇒ 9a² – 30bc + 25c² = (3b – 5c)²

⇒ 16a² – (3b – 5c)²

We know that,

(a + b)(a – b) = a² – b²

(4a + 3b – 5c) (4a – 3b + 5c)