若2x+5y-4z=0,3x+9y-7z=0,则x+y-z的值为
若2x+5y-4z=0,3x+9y-7z=0,则x+y-z的值为
若4x=7y+5z,2x+y=z,则x:y:z的值为
已知x+4y+3z=3x-2y-5z=0,求x+2y-z/2x-3y+7z的值
若x:y:z=3:5:7,3x+2y-4z=9,则x+y+z的值为( )
若5分之x=4分之y=3分之z(z不等于0),则3x-2y分之x+y+z的值为
若x/2=y/3=z/4不等于0,求x+y+z/x+y-z的值
2x+5y+4z=0,3x+y-7z=0,则x+y-z=?
若2x+5y+4z=0,3x+y-7z=0,则x+y-z的值等于( )
已知4x-3y-6z=0,x+2y-7z=0,且x、y、z都不为0,求(3x+2y+z)/(x+2y+3z)的值 快帮求
已知4x-3y-6z=0 ① ,x+2y-7z=0 ②,且x,y,z均不为0,求3x+2y+z÷x+2y+3z的值
已知{3x+4y+5z=0,2x+3y-4z=0,求x+y+z/x-y+z的值.
已知2x+3y-4z=0,3x+4y+5z=0,求x+y+z/(除以)x-y+z的值.