SOLUTION: what is 3i/7-8i???

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Question 307026: what is 3i/7-8i???
Answer by jim_thompson5910(35256) About Me  (Show Source):
You can put this solution on YOUR website!
%283i%29%2F%287-8i%29 Start with the given expression.


%28%283i%29%2F%287-8i%29%29%28%287%2B8i%29%2F%287%2B8i%29%29 Multiply the fraction by %287%2B8i%29%2F%287%2B8i%29.


%28%283i%29%287%2B8i%29%29%2F%28%287-8i%29%287%2B8i%29%29 Combine the fractions.


%28%283i%29%287%29%2B%283i%29%288i%29%29%2F%28%287-8i%29%287%2B8i%29%29 Distribute.


FOIL the denominator.


%2821i%2B24i%5E2%29%2F%2849%2B56i-56i-64i%5E2%29 Multiply.


%2821i%2B24%28-1%29%29%2F%2849%2B56i-56i-64%28-1%29%29 Replace i%5E2 with -1.


%2821i-24%29%2F%2849%2B56i-56i%2B64%29 Multiply


%28-24%2B21i%29%2F%28113%29 Rearrange and combine like terms.


-24%2F113%2B%2821%2F113%29i Break up the fraction.


So %283i%29%2F%287-8i%29=-24%2F113%2B%2821%2F113%29i.