Question

Solve the following system of linear equations by substitution method.
$2x+3y=9$
$4x+9y=18$

Answer 1

Given,

$2x+3y=9$......(1) and $4x+9y=18$.....(2).

or, $x=\frac{9-3y}{2}$.

Now substituting the value of $x$ in (2) we get,

$2(9-3y)+9y=18$

or,$3y=0$

or, $y=0$.

Now $y=0$ gives $x=\frac{9}{2}$. [ From (1)]

So $x=\frac{9}{2},y=0$.