若 |x-2|+|y+3|+|z-5|=0
若4x-3y-6z=0,x+2y-7z=0,求代数式5x*5x+2y*2y-z*z/2x*2x-3y*3y-10z*10
若x+2y-9z=0,x-2y+5z=0,(x.y.z≠=0)求2x平方+3y平方+7z平方/x平方-4y平方+4z平方
若2x+5y+4z=0 ,3x+y=0;则x+y-z=?
若x/3=y/2=z/5,则2x-3y-z/x-y+z=
x+y-z=0 2x-3y+2z=5 x+2y-z=3
2x+5y+4z=0,3x+y-7z=0,则x+y-z=?
若x/3=y/4=z/5,求x+y+z/3x-2y+z的值.
若x/2=y/3=z/4不等于0,求x+y+z/x+y-z的值
已知方程组4x-5y+2z=0 x+2y=3z 则x:y:z
已知3x-2y-5z=0,2x-5y+4z=0,且x,y,z均不为0,求3x*x+2y*y+5z*z/5x*x+y*y-
若{x+3y+10z=0 则 (x+y-z)/(x-y+z)
x/2=y/3=z/5 x+3y-z/x-3y+z