一道方程组 x^2-xy-2y^2+2x+3y-3=0 x^2+2xy+4Y^2+2x-6y+6=0
求方程组的解,方程组xy/(2x+y)-xy/(2x-y)=3,xy/(2x-y)+xy/(2x+y)=4
已知3x^2+xy-2y^2=0,求{(x+y)/(x-y)+4xy/(y^2-x^2)}/{(x+3y)*(x-y)}
(x-2xy)*(-xy+2y*y)-(3x*x-2xy)(x-9xy+6y*y)
解方程组 4x^2-y=0 3x^2+xy+x-2y+6=0
解方程组 x^2+2xy+y^2=9,(x-y)^2-4(x-y)+3=0
已知x*x-4xy+4y*y=0 求[2x(x+y)-y(x+y)]/(4x*x-4xy+y*y)的值?
x^+2xy+y^+4=16 x^-2xy+y^=16 求(3xy+6y^)+|x^-(2xy+2y^-3x^)|的值
已知xy=-2,x-y=3,求(x+y)(x-y)-y^2+(x-y)^2-(6x^2y-2xy^2)÷2y
(x-2)(y+3)=xy (x-5)(y+2)=xy 解方程组
已知3x*+xy-2y*=0,求(x/y)-(y/x)-(x*+y*)/(xy)的值.*是平方
解方程组x^2+3xy-4y^2=0,x^2-4xy+4y^2=25
化简:x-y/x+3y÷x^-y^2/x^2+6xy+9y^2-(xy/x+y)