SOLUTION: Multiply (5a - 3b)^2 Is this correct 25a^2 - 9b^2 Thanks

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Question 48499: Multiply
(5a - 3b)^2
Is this correct 25a^2 - 9b^2
Thanks

Answer by tutorcecilia(2152) About Me  (Show Source):
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Multiply
(5a - 3b)^2
Is this correct 25a^2 - 9b^2
Thanks
Almost, you may be thinking of the difference of two squares, that is:
(5a-3b)(5a+3b) = %2825a%5E2-15ab%2B15ab-9b%5E2%29 = %2825a%5E2-9b%5E2%29
.
The difference in this problem is that the entire quantity is taken twice:
%28%285a-3b%29%5E2%29 = (5a-3b)(5a-3b) [Use FOIL to solve]
%2825a%5E2+-15ab-15ab%2B9b%5E2%29 [Simplify]
%2825a%5E2-30ab%2B9b%5E2%29