The first step is to multiply the fraction by (3 +3i) / (3 +3i) to delete the i terms from the denominator:
[tex] \frac{ \sqrt{-16} }{3-3i} . \frac{3+31}{3+3i} +1-2i= \frac{4i(3+3i)}{9+9} +1-2i= \frac{12i-12}{18} +1-2i=[/tex]
[tex] \frac{12i-12+18-36i}{18} = \frac{6-24i}{18} = \frac{1}{3} - \frac{4}{3} i[/tex]