Question 881926
Remove the parenthesis. Then group and combine like terms.



{{{(4x^2-8xy+y^2)+(-8x^2-3xy-y^2)+(x^2+xy-2y^2)}}}



{{{4x^2-8xy+y^2-8x^2-3xy-y^2+x^2+xy-2y^2}}}



{{{(4x^2-8x^2+x^2)+(-8xy-3xy+xy)+(y^2-y^2-2y^2)}}}



{{{(-3x^2)+(-10xy)+(-2y^2)}}}



{{{-3x^2-10xy-2y^2}}}



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{{{(4x^2-8xy+y^2)+(-8x^2-3xy-y^2)+(x^2+xy-2y^2)}}} simplifies to {{{-3x^2-10xy-2y^2}}}