Question

Factorise the following:

72x² – 50y²

Answer 1

The given expression is,

72x² – 50y²

= 2(36x² – 25y²)

Here we use the identity

a² – b² = (a + b)(a – b)

Taking a = 6x and b = 5y, we get

∴ 72x² – 50y²

= 2((6x)² – (5y)²)

= 2(6x – 5y) (6x + 5y)

Therefore, the factors of the given expression are 2(6x – 5y) (6x + 5y)