Question

Factorise : 2ax+3ay-2bx-3by

Answer 1

I just look for things that two or more terms might have in common:
I notice the first and third terms have a 2x in common,
and the second and fourth terms have a 3y in common.
So:
2x (a-b) + 3y (a-b)
Then, I notice the common (a-b), so factor that out too:
(a-b)(2x-3y)