Question

Find the value of $x-y$ if $4x+3y=25$, $3x+4y=24$.

Answer 1

Given,

$4x+3y=25$ ------(1)

$3x+4y=24$ ------(2)

Multiply first equation by $3$ and second by $4$.

$12x+9y=75$

$12x+16y=96$

Subtracting first equation from second

$7y=21$

$y=3$

put $y=3$ in eqn (1) we get,

$x=4$

Now,

$x-y=4-3=1$