Question

Solve the following pair of equations :

$\frac{x-y}{6}=2(4-x)$

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

• A. $x=3,y=4$
• B. $x=1,y=-3$
• C. $x=-5,y=11$
• D. $x=3,y=-9$

Answer 1

Answer: (D)

$x=3,y=-9$

$\frac{x-y}{6}=2(4-x)\Rightarrow x-y=48-12x\Rightarrow 13x-y=48$ ...(i)

$2x+y=3(x-4)\Rightarrow 2x+y=3x-12\Rightarrow x-y=12$ ...(ii)

On subtracting (ii) from (i), we get
$12x=36\Rightarrow x=3$
On putting $x=3$ in (ii), we get
$3-y=12\Rightarrow y=-9$
Therefore, $x=3,y=-9$