Question

Solve the following pair of equations by substitution method
$2x+5y=2$ and $x+2y=3$

Answer 1

We have $2x+5y=2$ ..... (1)

$x+2y=3$ ....... (2)

Equation (2) becomes, $x=3-2y$ ........ (3)

Substituting x in (1) we get, $2(3-2y)+5y=2$

$\Rightarrow 6-4y+5y=2$

$-4y+5y=2-6$

$\therefore y=-4$

Substituting $y=-4$ in (3), we get, $x=3-2(-4)=3+8=11$

$\therefore$ The solution is x = 11 and y = - 4