SOLUTION: Find the product (2x-4y)(2x+4y)

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Question 404648: Find the product
(2x-4y)(2x+4y)
Answer by jsmallt9(3758) About Me  (Show Source):
You can put this solution on YOUR website!
(2x-4y)(2x+4y)
The slow way to multiply this is with FOIL. The faster way is to recognize that this expression fits the pattern %28a%2Bb%29%28a-b%29+=+a%5E2-b%5E2 with the "a" being 2x and the "b" being 4y. Using this pattern:
%282x-4y%29%282x%2B4y%29+=+%282x%29%5E2+-+%284y%29%5E2+=+4x%5E2+-+16y%5E2

FOIL should give you the same answer but after more work.