求9x*(-2x^2-xy+y^2)*(-xy)的值
已知x-xy=8,xy-y=-9,求x+y-2xy的值
1.已知x--xy=8,xy--y=--9,求x+y--2xy的值
如果x^2+xy+y-14,y^@+xy+x=28,求x+y的值.
已知xy^2=-2,求-xy(x^2y^5-xy^3-y)的值.
已知X+Y=3XY,求2X+2Y-XY除以X+Y+2XY的值,要算理.
已知x-y=4xy,求x-2xy-y分之2x+3xy-2y的值!
已知x+y=3xy,求2x+2y-xy/x+y+2xy的值、
若(y-x)/xy=3,求分式(2x+3xy-2y)/(x-2xy-y)的值
已知x-y/xy=3,求分式2x+3xy-2y/x-2xy-y的值.
若x+y-5xy=0,求(2x-3xy+2y)/(x+2xy+y)的值
已知3x=xy+3y,求2x+xy-2y/y-x-xy的值
已知xy/x+y =3,求2x-3xy+2y/-x+3xy-y 的值.