Question

Solve the following linear equations.
$x-y=3;4x+2y=0$

Answer 1

$x-y=3$ ........$\left(1\right)$

$4x+2y=0$

or $2x+y=0$ ........$\left(2\right)$

Eqn$\left(2\right)+\left(1\right)$

$\Rightarrow 2x+y+x-y=0+3=3$

$3x=3$

$\therefore x=\frac{3}{3}=1$

substitute $x=1$ in $\left(2\right)$ we get

$2x+y=0\Rightarrow 2\times 1+y=0$

$\Rightarrow y=-2$

$\therefore x=1,y=-2$