# How do you divide (-1)/(-9i)?

$- \frac{i}{9}$.
$\frac{- 1}{- 9 i} = \frac{1}{9 i} = \frac{1}{9 i} \cdot \left(\frac{i}{i}\right) = \frac{i}{9 {i}^{2}} = \frac{i}{9 \left(- 1\right)} = - \frac{i}{9}$.