Question

Solve
$4x-5y+33=0$
$20x-9y=107$
Find $x$ and $y$.

Answer 1

The equations are given as,

$4x-5y=-33$ ..................(i)

And, $20x-9y=107$ ......................(ii)

Multiply equation (i) by $5$, we get

$20x-25y=-165$ ...............(iii)

On subtracting (iii) from (ii), we get

$\Rightarrow$ $20x-9y-(20x-25y)=107-(-165)$

$\Rightarrow$ $20x-9y-20x+25y=107+165$

$\Rightarrow$ $15y=272$

$\therefore$ $y=17$

Putting the value of $y=17$ in (i), we get

$x=13,y=17$