（1）8x-(-3x-5) = 8x+3x+5=11x+5
(2)1-(x-2y^2)+(-x+y^2)= 1-x+2y^2-x-y^2 = 1-2x+y^2
(3)(4y+3)-(5y-2)= 4y+3-5y+2=5-y
(4)(2x-3y)-(5x-y)=2x-3y-5x+y= -3x-2y
(5)-(xy-2z)+(-xy+3z) = -xy-+2z-xy+3z = -2xy+5z
(6)-(x^2+y-4y^2) = -x^2 - y +4y^2
不理解就追问,理解了请采纳!第五小题怎么回事(5)-(xy-2z)+(-xy+3z) = -xy+2z-xy+3z = -2xy+5z多打了个负号。