Answer
$$\frac{10}{yx}$$
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:
$$\frac{5}{y}\times \frac{2}{x}\\ \frac{5\times \:2}{yx}\\ \frac{10}{yx}$$