x+y+z=什么 x=123 y=124 z=125分之1

若z分之x+y+z=y分之x-y+z=x分之-x+y+z,求xyz分之(x+y)(y+z)(z+x) x分之y+z=y分之z+x=z分之x+y(x+y+z不等于0）,求x+y+z分之x+y-z (x+y-z)(x-y+z)= X+Y+Z=? 已知x+y+z=0,求(y²+z²-x²)分之1+(z²+x²-y&# 已知x,y,z满足x/(y+z)+y/(z+x)+z/(x+y)=1,求代数式x2/(y+z)+y2/(x+z)+z2/ 已知实数x,y,z满足x/(y+z)+y/(z+x)+z/(x+y)=1,求x2/(y+z)+y2/(z+x)+z2/( 已知x:：y：z=3：4：5,(1)求x+y分之z的值；（2）若x+y+z=6,求x,y,z. 2分之x=3分之y=5分之z x+y+z=20 求x,y,z 挺急的~已知Z分之X+Y-Z=y分之X-Y+Z=X分之-X+Y+Z且XYZ分之(X+Y)(X+Z)(Y+Z)=-1.x+ 已知 x/(y+z)+y/(z+x)+z/(x+y)=1 x+y+z=1 求xyz/(x+y)(y+z)(z+x)的最大值