Answer
$$=\frac{x}{2y}$$
Work Step by Step
Recall, one never divides by a fraction. Rather, if we want to divide by a fraction, we multiply by the reciprocal of the fraction. Thus, we find:
$$ \frac{\frac{x}{2}}{y} \\ \frac{x}{2} \cdot \frac{1}{y} \\ =\frac{x}{2y}$$