(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!
(5)-(xy-2z)+(-xy+3z)=-xy+2z-xy+3z=-2xy+5z多打了个负号。