解方程组{3x^2-2xy-y^2+4x+7y=13,4x+y=7
求方程组的解,方程组xy/(2x+y)-xy/(2x-y)=3,xy/(2x-y)+xy/(2x+y)=4
解方程组x+y+xy=7 x^2+y^2+xy=13
解方程组:3x^2-y=8& x^2+xy+y=4
解方程组2x*+2xy+4y*+x=19;x*+xy+2y*-y=9
解方程组 x^2+2xy+y^2=9,(x-y)^2-4(x-y)+3=0
解方程组:(x-1)(y-2)=xy和x(x+2)-4y(y-1)=(x+2y)(x-2y)
解方程组{(x-1)(y-2)=xy {x(x+2)-4y(y-1)=(x-2y)(x+2y)
解方程组:(x-1)(y-2)=xy,x(x+2)-4y(y-1)=(x+2y)(x-2y)
解方程组(x+y)(x-2y)=-5 (x-y)(x+2y)=7
(x-2)(y+3)=xy (x-5)(y+2)=xy 解方程组
解方程组(要过程)x^2+y^2=10 x+xy+y=7
解方程组x^2+3xy-4y^2=0,x^2-4xy+4y^2=25