<PRE><B>Question 800888</B>
factor completely
x^12 y^10 +8x^6 y^5 z -9z^2
Please explain how i get this answer 
My teacher has the answer as (x^6 y^5+ 9z)(x^6 y^5 -z)
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x^12*y^10 + 9x^6y^5z - x^6y^5z - 9z^2
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Factor by pairs::
x^6y^5(x^6y^5+9z) -z(x^6y^5 + 9z)
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Factor again::
(x^6y^5+9z)(x^6y^5-z)
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Cheers,
Stan H.</PRE>