Question

Solve the following pair of equations:

$7x-8y=-12$

$-4x+2y=3$

• A. $x=0,y=0$
• B. $x=0,y=\frac{3}{2}$
• C. $x=\frac{5}{2},y=4$
• D. $x=6,y=\frac{1}{2}$

Answer 1

The correct option is B $x=0,y=\frac{3}{2}$

We have
$7x-8y=-12$ … (1)
$-4x+2y=3$ … (2)

Multiplying equation (2) by 4, we have
$-16x+8y=12$ ... (3)

Adding equations (1) and (3), we get
$-9x=0$
$\Rightarrow x=0$

Putting $x=0$ in equation (2), we get
$2y=3$
$\Rightarrow y=\frac{3}{2}$

$\text{Hence,}x=0,y=\frac{3}{2}$