Question

Factorise ax+by+ay+bx

Answer 1

you can write
\[a(x+y)+b(x+y)\] as a first step

Answer 2

=a(x+y) + b(x+y)
= (x+y)(a+b)

Answer 3

then see that you have a common factor of
\[x+y\] giving
\[(a+b)(x+y)\]