Question

$\text{Find the value of}x\text{and}y\text{if}x+y=18$
$\text{and}x-2y=0.$

• A. $x=12\&y=6$
• B. $x=6\&y=12$
• C. $x=11\&y=7$
• D. $x=7\&y=11$

Answer 1

The correct option is A $x=12\&y=6$

Given $x+y=18---\left(i\right)$ and
$x-2y=0---\left(ii\right)$
Using elimination method,
$\left(i\right)-\left(ii\right)\Rightarrow 3y=18$
$y=6$
Substitute the value of $y$ in $\left(i\right)$
$\to x+6=18$
$x=12$

$\therefore x=12\&y=6$