Question 631009
Solve. 
1. 9-4x²+4xy-y²
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9 - (4x^2-4xy+y^2)
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9 - (2x-y)^2
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= [3-(2x-y)]*[3+(2x-y)]
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= (3-2x+y)(3+2x-y)
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2. x²+2x+1-y²
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(x+1)^2 - y^2
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= (x+1-y)(x+1+y)
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Cheers,
Stan H.
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