Question

x(x-1)-y(y-1) factorise

Answer 1

Answer:

x(x - 1) - y(y - 1) = (x - y)(x + y - 1)

Step-by-step explanation:

x(x - 1) - y(y - 1) = x² - x - y² + y

                       = x² - y² - x + y

                       = (x + y)(x - y) - (x - y)

                       = (x - y)(x + y - 1)