Factories: 9a 2 – b 2 + 4b – 4

Question

Factories: 9a 2 &#x2013; b 2 + 4b &#x2013; 4

Philoid · Accepted Answer

Given,

9a² – b² + 4b – 4

= 9a² – (b² – 4b + 4)

By using the formula a² – b² = (a + b)(a – b)

We get,

9a² – b² + 4b – 4 = 9a² – (b² – 4b + 4)

= (3a)² – (b – 2)²

= {3a + (b – 2)}{3a – (b – 2)}

= (3a + b - 2)(3a – b + 2)