SOLUTION: (3-2√7)(3+2√7)

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Question 422153: (3-2√7)(3+2√7)
Found 2 solutions by unlockmath, jsmallt9:
Answer by unlockmath(1688) About Me  (Show Source):
You can put this solution on YOUR website!
Hello,
Let's distribute this (3-2√7)(3+2√7) out so we have:
9+6√7-6√7-28
Combine like terms and we get:
-19
There we go.
Make sense?
RJ
www.math-unlock.com

Answer by jsmallt9(3758) About Me  (Show Source):
You can put this solution on YOUR website!
%283-2sqrt%287%29%29%283%2B2sqrt%287%29%29
You could use FOIL to multiply these.

But your expression fits the %28a-b%29%28a%2Bb%29+=+a%5E2-b%5E2 pattern so we can use the pattern to multiply, too. I like using the patterns. So

which is the same answer you would get from FOIL (if you do it correctly).