Question

Solve the following systems of equations by the method of cross-multiplication:
$2x-y=6$
$x-y=2$

Answer 1

Bring constant to LHS side

$2x-y-6=0$
$x-y-2=0$

By method of cross multiplication :

$\Rightarrow \frac{x}{(-1\times -2)-(-1\times -6)}=\frac{y}{(-6\times 1)-(-2\times 2)}=\frac{1}{(2\times -1)-(1\times -1)}$

$\Rightarrow x=\frac{-4}{-1}=4$

$\Rightarrow y=\frac{-2}{-1}=2$