Question

factorise 25(3x+y)² - 40(3x+y)(x-2y) + 16(x-2y)²

Answer 1

it is easy cause it is similar to identity -> a^2-2ab+b^2 =(a+b)^2
so, 25(3x+y)^2 is square of 5(3x+y) and 16(x-2y)^2=4(x-2y)
thus ur answer is---> [5(3x+y) - 4(x-2y)]^2=[15x+5y-4x+8y]^2
=[11x+13y]^2

hope this helps!!
plz mark me as brainliest!

Answer 2

let 3x+y be a and x-2y be b
25a^2-40ba+16b^2
25a^2-20ba-20ba+16b^2
5a(5a-4b)-4b(5a-4b)
(5a-4b)^2

hope it helps you