Question

Help me please 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)

Answer 1

(x - y)(a + b)

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.