Question

Factorise the following expressions:-
$x(a-1)+y(1-a)$

Answer 1

$x(a-1)+y(1-a)$

$\Rightarrow ax-x+y-ay$

$\Rightarrow ax-ay-x+y$

$\Rightarrow a(x-y)-1(x-y)$

$\Rightarrow (a-1)(x-y)$