2(x+y)等于2xy/(x+y)为什么?
4x+2xy+y等于
x根号x+x根号y/xy-y^2)-(x+根号xy+y/x根号x-y根号)y
已知X+Y分之XY等于3,求-X+3XY-Y分之2X-3XY+2Y
x-y/x²÷x²-2xy+y²/xy*(xy-x²)
由已知x+y=-2,xy=3那么2(x+xy)-[(xy-3y)-x]-(-xy)等于多少?
(x+2y-3y)- (-2x-y+xy ) 其中x+y=0.5 xy等于-0.5
(xy-x^2)乘以(xy)/(x-y)
2x(x²y-xy²)+xy(xy-x²)]÷x²y等于多少
(x^2+xy/x-y)/(xy/x-y)计算
x平方-2x除以2y-xy等于多少,
已知x+3y=12,则(x平方+2xy - 3y平方)除以(x-y)等于多少
整数x,y满足方程2xy+x+y=83,则x+y等于多少?(两个答案)