若x-2y=7 xy=3 则2xy-4y+2x+5=?
已知x-y=4xy,则2x+3xy-2yx-2xy-y
若x+y=-1,则x^4+5x^3y+x^2y+8x^2y^2+xy^2+5xy^3+y^4=( )
(-3x^y+2xy)-( )=4x^+xy
若x+y分之xy=2,则-x+3xy-y分之3x-xy+3y=多少?
xy=-2,x+y=3,求代数式(4xy+12y)+[7x-(3xy+4y-x)]
若x+y-5xy=0,求(2x-3xy+2y)/(x+2xy+y)的值
已知xy/x+y=1/2,则代数式3x-5xy+3y/-x+3xy-y=
x+y=8,xy=-2,求(5xy+4x+7y)+(6x-3xy)-(4xy-3y)的值
若x-y=4,xy=1,求(-2xy+2x+3y)-(3xy+2y-2x)-(x+4y+xy)的值
[-(x-y)^2/xy]^-4*(y^2-xy/x)^3*(x^4/y^10)÷(xy-y^2/x)^-5=-y(y-
若(3xy+2)+|7-x-y|=0,求代数式(5xy+10y)-[-5x-(4xy-2y+3x)]的值.
若1/x+1/y=2,则(2x-xy+2y)÷(3x+5xy+3y)