SOLUTION: . Multiply. (5x + 9)^2

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Question 89360: . Multiply. (5x + 9)^2
Answer by jim_thompson5910(35256) About Me  (Show Source):
You can put this solution on YOUR website!
Start with the given expression

%285x%2B9%29%285x%2B9%29

When you FOIL, you multiply the terms in this order:
F-First (i.e. you multiply the first terms in each parenthesis which in this case are 5x and 5x)
O-Outer (i.e. you multiply the outer terms in each parenthesis which in this case are 5x and 9)
I-Inner (i.e. you multiply the inner terms in each parenthesis which in this case are 9 and 5x)
L-Last (i.e. you multiply the last terms in each parenthesis which in this case are 9 and 9)


So lets multiply the first terms:
5x%2A5x=25x%5E2 multiply 5x and 5x to get 25x%5E2



So lets multiply the outer terms:
5x%2A9=45x multiply 5x and 9 to get 45x



So lets multiply the inner terms:
9%2A5x=45x multiply 9 and 5x to get 45x



So lets multiply the last terms:
9%2A9=81 multiply 9 and 9 to get 81

Now lets put everything together
%285x%2B9%29%285x%2B9%29=25x%5E2%2B45x%2B45x%2B81=25x%5E2%2B90x%2B81

So the expression

%285x%2B9%29%285x%2B9%29

FOILs to:

25x%5E2%2B90x%2B81

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