Question

Factorise 25a^2-b^2+14bc-49c^2

Answer 1

Answer:

(5a-b-7c) (5a+b-7c)

Step-by-step explanation:

= 25a^2-b^2+14bc-49c^2

= (5a)^2-(b)^2+14bc-(7c)^2

= (5a)^2-{(b)^2+14bc-(7c)^2}

= (5a)^2- (b^2)-14bc+(7c)^2

= (5a)^2-(b-7c)^2

= (5a-b-7c) (5a+b-7c)

Ok, this is your correct answer.