若|x+(-2)|+|y+3|+|z|=0,求x+y+z的值

若x+y+z=3y=2z,则x/x+y+z=? 若|x+3|+|y-2|+|2×z+1|=0求(x×z-y×z)(y-x+z)的值 试证明(x+y-2z)+(y+z-2x)+(z+x-2y)=3(x+y-2z)(y+z-2x)(z+x-2y) 已知(x+y)(x+z)=x,(y+z)(y+x)=2y,(z+x)(z+y)=3z,求x,y,z 若X:Y:Z=5:6:7那么(Y-X):(Y+Z)和(X+2Y+3Z):(3X+2Y+Z) 若x/2=y/3=z/4,则3x-2y+5z/x+y+z= 若x/3=y/2=z/5,则2x-3y-z/x-y+z= 若2x=3y=5z,则3x-2y+z/x+y-z 若方程组2x+3y-z=0,x-3y-z=0,则x：y：z=? 若x:y:z=3:2:1,则x+2y-z/2x-y+z= 若xyz=1,求证 x^2/(y+z)+y^2/(z+x)+z^2/(x+y)≥3/2 若x/3=y/4=z/5,求x+y+z/3x-2y+z的值. 若x:y:z=2:3:4,求x+y+z/x-2y+3z的值 若方程组：x+y-2z=0,3x+y-z=0,则x：y：z= 若x/2=y/3=z/4不等于0,求x+y+z/x+y-z的值 若xyz≠0且4(x/z)-5(y/z)=-2,(x/z)+4(y/z)=3,求x:y:z 若4x-3y-6z=0,x+2y-7z=0,则x+y+z/3x-y+z=? 若{x+3y+10z=0 则 (x+y-z)/(x-y+z){2x-y-2z=0