SOLUTION: What is ( 7-4i/9+2i)

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Question 578748: What is ( 7-4i/9+2i)
Answer by dfrazzetto(283) About Me  (Show Source):
You can put this solution on YOUR website!
To get rid of the complex term in the denominator, multiply top and bottom by the conjugate (9-2i)
%287-4i%29%2F%289%2B2i%29+%2A+%289-2i%29%2F%289-2i%29
That gives us 81 - 4(i^2) = 81 + 4 = 85 in the denominator
In the numerator, use Use FOIL:
(7-4i)(9-2i) = 63 -14i -36i +8i^2; i^2=-1, so:
= 63 - 50i - 8 = 55 - 50i
%2855-50i%29%2F%2885%29 Divide through by 5
%2811-10i%29%2F%2817%29