Question

factorise the following expressions
25(a+b)^2-16(a-b)^2
Please Help​

Answer 1

Answer:

25(a+b)^2 - 16(a-b)^2

=> [ 5(a+b)]^2 - [ 4(a-b)]^2

=> (5a +5b)^2 - (4a-4b)^2

=> (5a +5b - 4a +4b) ( 5a +5b +4a - 4b)

=> (a +9b) (9a+b)