# How do you simplify (6 + 6i ) / (7 + 6i )?

$\frac{42 + 42 i - 36 i + 36}{49 + 36} = \frac{78 - 6 i}{85}$
$= \frac{78}{85} - \frac{6}{85} i$
This can be put in trignometric form $r \left(\cos \theta - i \sin \theta\right)$ if required, by solving $r \cos \theta = \frac{78}{85}$ and $r \sin \theta = - \frac{6}{85}$.