9/25 xsquare - 16/169 ysquare

Question

_{i have to factorise this}

Answer 1

It appears you are factoring the difference of two squares.

 

when you have two perfect squares separated by a minus sign, you take the square root of each term and factor as follows:

 

x^2 - Y^2 ---->  (x-y)(x+y)

 

In your question, all the numbers and variables are perfect squares

 

9/25x^2 - 16/169y^2  ---->  (3/5x-4/13y)(3/5x+4/13y)