Answer
$y=\dfrac{3x}{a-1}$
Work Step by Step
Put all the terms with $y$ on the left side of the equation:
$ay+2x=y+5x
\\ay+2x-2x-y=y+5x-2x-y
\\ay-y=3x$
Factor out $y$ on the left side of the equation:
$y(a-1)=3x$
Divide $a-1$ to both sides of the equation:
$\dfrac{y(a-1)}{a-1}=\dfrac{3x}{a-1}
\\y=\dfrac{3x}{a-1}$
