已知1/x-1/y=-3,则x+5xy-y/3x-2xy-3y=
已知xy/x+y=1/2,则代数式3x-5xy+3y/-x+3xy-y=
已知3/(x-y)=1/xy 求(-x-2xy+y)/ (2x+3xy-2y)
已知:x-y=1,xy=-2.求:(-2xy+2x+3y)-(3xy+2y-2x)-(x+4y+xy)的值
.已知:x-y=1,xy=-2.求:(-2xy+2 x+3y)-(3xy+2y-2x)-(x+4y+xy)的值
已知1/x=1/y=6,则3x-2xy+3y/3xy+x+y=?
已知1/x+1/y=5 求2x-3xy+2y/3x+2xy+3y
已知1/x+1/y=3,求(3x-5xy+3y)/(x-2xy+y)
已知1/X-1/Y=-2,求3X-5XY-3Y/-X+3XY+Y的值
已知1/x-1/y=3,求x-2xy-y/5x+3xy-5y的值
已知1/x-1/y=-3,则5x+xy-5y/x-xy-y的值为
已知1/x=1/y+3,则(5x+xy-5y)/(x-xy-y)的值为( )
已知1/x减1/y=-3,则(2x+xy-2y)/x-xy-y的值为