You can put this solution on YOUR website! factor ym(xm-xmy ^2)
The two terms in the parenthesis have a common factor of xm; factor it out:
= ym[(xm)(1-y^2)]
= xym^2(1-y^2)
The parenthesis contains the "difference of squares" which can be factored:
= xym^2(1-y)(1+y)
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Cheers,
Stan H.
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