xy=(x+10)*(y-0.2) xy=(x-4)*(y+0.1)要讲清楚步骤（我上六年级＾＿＾）,

|x|/x+y/|y|+xy/|xy|= 计算：( 根号xy-xy/x+根号xy)÷根号xy-y/x-y= 已知x-xy=10,xy-y=2,则x-y=（ ）,-2xy+x+y=（ ）. 已知x-xy=20,xy-y=-10,则x-y=( ),x+y-2xy=( ). 已知x-xy=20,xy-y=-10,则x-y=?,x+y-2xy? x y xy=10怎么算 【x(xy-xy)-y(x-xy)】÷3xy 证明|xy|=|x||y| xy-(x+y)=1000 证明|xy|=|x||y| 1*{x+y+xy=7{x2+y2+xy=132*{x2+y2=10{x+xy+y=7 已知2x+xy=10,3y+2xy=6.求4x+8xy+9y=? [(xy+2)(xy-2)-2x^2y^2+4]/xy,其中x=10,y=-1/25 [(xy+2)(xy-2)-2x^2y^2+4]/xy,其中x=10,y=-1/25 [(xy+2)(xy-2)-2x^2y^2+4]/xy(其中x=10y=25分之一) 已知x-y=3,xy=10,则x²y-xy²= 如果X+Y=10 XY=7则X~2Y+XY~2=? xy=(x-10)(y+1) xy=(x-15)(y+3) 解方程组.