Question 371648
Factor completely: 
x^2 - 2x + y^2 + 2y - 2xy - 15
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Rearrange:
x^2-2xy+y^2 -2(x-y) - 15
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(x-y)^2 -2(x-y) - 15
This is a quadratic with variable (x-y)
Factor:
[(x-y)-5][(x-y)+3]
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Cheers,
Stan H.