#### Answer

$\dfrac{1+7i}{5}$

#### Work Step by Step

Simplify. $ \dfrac{ 3+i}{1 -2i}$
Now, $ \dfrac{ 3+i}{1 -2i} = \dfrac{ 3+i}{1 -2i} \cdot \dfrac{ 1 +2i}{1 +2i}$
or, $=\dfrac{3+6i+i+2i^2}{1-(2i)^2}$
Since, $i^2=-1$
or, $=\dfrac{3+6i+i+2(-1)}{1-4(-1)}$
Hence,
$\implies\dfrac{1+7i}{5}$