x+y=10;xy=9
已知2x+xy=10,3y+2xy=6.求4x+8xy+9y=?
已知x-xy=8,xy-y=-9,求x+y-2xy的值
已知x+y=12,xy=9,求(x+3xy+y)/(xy+xy)的值
x y xy=10怎么算
xy+yx=10x,y是多少
已知x-y=3xy,且xy不等于0,则-3x+6xy+3y/(7x-5y)-9xy-(3x-y)
[-(x-y)^2/xy]^-4*(y^2-xy/x)^3*(x^4/y^10)÷(xy-y^2/x)^-5=-y(y-
解方程组一式4y+3x=10xy二式9y-7x=负5xy
xy=9,x-y=-3,则x平方+3xy+y平方=?
x*-2xy+3y*=9 4x*-5xy+6y*=30
{xy\x+y=6 xy\9x+4y=1
xy=(x-10)(y+1) xy=(x-15)(y+3) 解方程组.