Factorise: ax + bx - ay - by

1: (a-b) (x-y)

2: (a+b) (x+y)

3: (a+b) (x-y)

4: (a-b) (x+y)

(x - y)(a + b)

Step-by-step explanation:

Notice that x is common to the first two terms and that -y is common to the last two terms.  Thus, ax + bx is equivalent to x(a + b), and -ay - by is equivalent to -y(a + b).

(a + b) is common to both these results:  x(a + b) - y(a + b).  If we factor out (a + b), we get (x - y)(a + b).  Neither (1) nor (2) is correct.

ok so what's the question?

step-by-step explanation: