Question

Use elimination method for solving the following equations:
$x-y=7$, $3x+y=10$

Answer 1

Given equations are

$x-y=7$ ....(1)

and $3x+y=10$ ....(2)

Add equations (1) and (2) to eliminate $y$.

So, we have $4x=17$

$\Rightarrow x=\frac{17}{4}$

Substitute this value of $x$ in equation (1),

$\frac{17}{4}-y=7$

$\Rightarrow y=\frac{17}{4}-7$

$\Rightarrow y=\frac{17-28}{4}$

$\Rightarrow y=-\frac{11}{4}$

Therefore, the solution is $x=\frac{17}{4},y=-\frac{11}{4}$.