SOLUTION: factor 15x^2 -4xy -4y^2

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Question 297739: factor 15x^2 -4xy -4y^2
Found 2 solutions by user_dude2008, stanbon:
Answer by user_dude2008(1862) About Me  (Show Source):
You can put this solution on YOUR website!
15x^2 -4xy -4y^2 = 15x^2 -10xy+6xy -4y^2 = (15x^2 -10xy)+(6xy -4y^2) = 5x(3x-2y) + 2y(3x-2y) = (5x+2y)(3x-2y)

Answer by stanbon(75887) About Me  (Show Source):
You can put this solution on YOUR website!
factor 15x^2 -4xy -4y^2
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Think of two numbers whose product is 15*-4 = -60
and whose sum is -4
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The numbers are -10 and +6
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Rewrite the problem replacing -4xy by -10xy+6xy.
= 15x^2 - 10xy+6xy - 4y^2
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Factor:
5x(3x-2y) - 2y(3x+2y)
Factor again to get the final answer:
(3x+2y)(5x-2y)
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Cheers,
Stan H.