SOLUTION: 5x^2-20y^2

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Question 38200: 5x^2-20y^2
Answer by fractalier(6550) About Me  (Show Source):
You can put this solution on YOUR website!
From 5x^2 - 20y^2, we first factor out the 5 and get
5(x^2 - 4y^2)
But x^2 - 4y^2 is the difference of squares, and can be factored again...
5(x^2 - 4y^2) =
5(x + 2y)(x - 2y)