Question

How do we factorise 162-8r^2

Answer 1

162-8r²

by taking 2 common from both the terms , we have ,

=> 2 (81-4r²)

=> 2 [(9)² - (2r)²]

using a²-b² = (a+b)(a-b)


=> 2 [9-2r][9+2r]

=> 2 (9-2r)(9+2r)

hope this helps