Answer
$x=\frac{a(y+b)}{b}$
Work Step by Step
$\frac{x}{a}-1=\frac{y}{b}$
Add 1 to both sides.
$\frac{x}{a}=\frac{y}{b}+1$
1 is also equal to $\frac{b}{b}$.
$\frac{x}{a}=\frac{y}{b}+\frac{b}{b}$
Add.
$\frac{x}{a}=\frac{y+b}{b}$
Multiply each side by a.
$x=\frac{a(y+b)}{b}$