Answer:
-x^8y^2 -2y^7 -2xy^4 -6xy
Step-by-step explanation:
Eliminate parentheses.
xy^4 + 5y^7 - 6xy - 7y^7 - x^8y^2 -3xy^4
Arrange in descending degree order, group like terms.
-x^8y^2 +(5y^7 -7y^7) +(xy^4 -3xy^4) -6xy
Combine like terms.
-x^8y^2 -2y^7 -2xy^4 -6xy
