已知x/3=y/4,则x-y/4x+3y=
已知x,y满足x²+y²-4x+6y+13=0则(3x+y)²-(3x+y)(3x-y)的
已知x-2y/2x+3y=3/4,则x:y=
已知x=1/3,y=-1/2,求代数式x-(x+y)+(x+2y)-(x+3y)+(x+4y)-(x+5y)+...-(
已知x/5=y/3,则(x/x+y)+(y/x-y)-(yxy/xxx-yxy)
已知2x-y/x+3y=2,求代数式4x-2y/x+3y减4x+12y除以2x-y
已知2x-y/x+3y=2,求代数式4x-2y/x+3y减4x+12y/2x-y的值
已知X+Y=-4,怎样求二分之一X+Y-4X-Y+3X+Y-二分之三X+Y+X-Y的值
已知3x^2+xy-2y^2=0,求{(x+y)/(x-y)+4xy/(y^2-x^2)}/{(x+3y)*(x-y)}
已知实数x.y满足根号(x+y-8)+根号(8-x-y)=根号(3x-y-4)+根号(x-2y+7),求x,y
已知x+y+2(-x-y+1)=3(1-y-x)-4(y+x-1),则x+y等于( )
已知x*x+4x+y*y-2y+5=0,则x*x+y*y=?
1.已知x-1/x+2=y-3/y-4,若用含x的代数式表示y,则y=