已知(x+y)^2=9,(x-y)^2=5,求xy的值
已知x-xy=8,xy-y=-9,求x+y-2xy的值
已知xy^2=-6,求-xy(x^3y^7-3x^2y^5-y)的值
已知x+y=-1,xy=-2,求代数式-5(x+y)+(x-y)+x(xy+y)的值
已知x-y=6,xy=-2,求3(xy+x-2y)-5(y-2x)+2(xy-x)的值.
已知xy=2,x-y=3,求(x+y)(x-y)-y^2-(6x^2y-2xy^2)/2y的值.
已知xy=-2,x-y=3,求(x+y)(x-y)-y平方+(x-y)平方-(6x2y-2xy平方)/2y的值
已知x^2+xy-2y^2=0 (x不等于0,y不等于0),求x/y-y/x-(x^2+y^2)/xy的值
初中数学分式已知x/y=2,求(x*x-xy+3y*y)/x*x+xy+6y*y的值
已知xy/x+y=2,求代数式3x-5xy+3y/-x+2xy-y的值
已知xy=2(x+y),求(5x-xy+5y)/(3xy-x-y)的值
已知x-y=2xy,求代数式3x-5xy-3y/x+xy-y的值
已知X+Y=2XY,求4X-5XY+4Y 除以X+XY+Y 的值