Question 7853
The goal here is to get the complex number out from under.  You can do this by multiplying the denominator by its complex conjugate which is: 3-5i

{{{(2-4i)/(3+5i) = ((2-4i)(3-5i))/((3+5i)(3-5i))}}} = {{{(6-22i+20i^2)/(9-25i^2)}}} = {{{(-14-22i)/(9+25)}}} = {{{-(14+22i)/34}}} = {{{-(7+11i)/17}}}