Question 217390
(x^2+3xy-8y^2) - (6x^3 +8xy+xy^2),,,,distribute  the  -1
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x^2 +3xy -8y^2 -6x^3 -8xy -xy^2,,,,rearrange
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-6x^3 + x^2 -8xy+3xy -xy^2 - 8y^2,,,combine  like  terms
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-6x^3 +x^2 -5xy -xy^2 -8y^2,,,,,,
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