SOLUTION: Please help with this one i keep getting stuck. (i+6)(3i-2)

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Question 130216: Please help with this one i keep getting stuck.
(i+6)(3i-2)
Answer by jim_thompson5910(35256) About Me  (Show Source):
You can put this solution on YOUR website!
%28i%2B6%29%283i-2%29 Start with the given expression


Now let's FOIL the expression



Remember, when you FOIL an expression, you follow this procedure:


%28highlight%28i%29%2B6%29%28highlight%283i%29-2%29 Multiply the First terms:%28i%29%2A%283i%29=3i%5E2


%28highlight%28i%29%2B6%29%283i%2Bhighlight%28-2%29%29 Multiply the Outer terms:%28i%29%2A%28-2%29=-2i


%28i%2Bhighlight%286%29%29%28highlight%283i%29-2%29 Multiply the Inner terms:%286%29%2A%283i%29=18i


%28i%2Bhighlight%286%29%29%283i%2Bhighlight%28-2%29%29 Multiply the Last terms:%286%29%2A%28-2%29=-12


3i%5E2-2i%2B18i-12 Now collect every term to make a single expression



3i%5E2%2B16i-12 Now combine like terms


3%28-1%29%2B16i-12 Replace i%5E2 with -1. Remember i%5E2=-1


-3%2B16i-12 Multiply


-15%2B16i Combine like terms

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Answer:
So %28i%2B6%29%283i-2%29 foils and simplifies to -15%2B16i

In other words, %28i%2B6%29%283i-2%29=-15%2B16i