Answer
-9/8
Work Step by Step
We never can divide by a fraction. Instead, we need to multiply the first fraction by the reciprocal of the second fraction. Because the reciprocal of -4/5 is -5/4, we obtain:
$\frac{9}{10}\times \frac{-5}{4} = \frac{-45}{40}=\frac{-9}{8}$
