若2x=6y=3z,且xy+yz++zx=99,求2x²+12y²+9z²的值

若x/3=y/1=z/2,且xy+yz+zx=99,求zx平方+9y平方+9z平方的值? (x+y-xy)/(x+y+2xy)=(y+z-2yz)/(y+z+3yz)=(z+x-3zx)/(z+x+4zx),且2/x=3/y=1/z,则xyz=? 已知（x+y-xy）/(x+y+2xy)=(y+z-2yz)/(y+z+3yz)=(z+x-3zx)/(z+x+4zx),且2/x=3/y-1/z,则xyz=? 若2x=6y=3z,且xy+yz+zx=99,求2x^2+12y^2+9z^2的值 若2x=6y=3z,且xy+yz++zx=99,求2x²+12y²+9z²的值 若x/3=y/2=z/5,且xy+yz+zx=93,求9x*x+12y*y+2z*z的值. 分式题:xy=x+y,yz=2(y+z),zx=3(z+x),求xyz/(xy+yz+xz)xy=x+y,yz=2(y+z),zx=3(z+x),求xyz/(xy+yz+xz) xy 2yz 3zx 4xyz________ = ________ = _______ = ___________ (xyz不等于0)x+y+xy y+z+yz z+x+zx xy+yz+zx最好有解题思路 算出 X Y Z 分别等于几 若x/3=y/1=z/2,且xy+yz+zx=99,那麽2x^2+12y^2+9z^2=? 若x/3=y/1=z/2,且xy+yz+zx=99,则2x^2+12y^2+9z^2= 若x:y:z=3:1:2,且zx-xy-yz=99,求2x^2+12y^2+9z^2的值 若x/3=y/2=z/5,且xy+yz+zx=93,求9x²+12y²+2z²的值. 若x+y+z=6,xy+yz+zx=11,xyz=6,则x/yz+y/zx+z/xy= 若x+y+z=6,xy+yz+zx=11,xyz=6,则x/yz+y/zx+z/xy= 若x+y+z=6,xy+yz+zx=11,x^3+y^3+z^3-3xyz 若3/x=2/y=5/z则xy+yz+zx/x^2+y^2+z^2=? XYZ满足XY/X+Y=-2,YZ/Y+Z=3/4,ZX/Z+X=-4/3,求XYZ/XY+YZ+ZX的值 若x/3=y/2=z/5则x^2-y^2-z^2/（xy+yz+zx）