Dividing Complex Numbers

How do you divide this: 4/(7 + 2i)?

   4
------
7 + 2i

4 (7 - 2i)
-------------  {multiplied top and bottom by "conjugate" of denominator}
(7 + 2i)(7 - 2i)

28 - 8i
-----------  {used distributive property on top, foil method on bottom}
49 - 4i² 

28 - 8i
------------  {i²  is -1, when dealing with imaginary numbers}
49 - 4(-1)

28 - 8i
----------- {multiplied -4 by -1}
49 + 4

  28 - 8i
----------  {added 49 and 4 on bottom}
     53


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