已知x:y:z=2:3:5,且3x+4z-2y=40,求x
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-
已知3x-2y-5z=0,2x-5y+4z=0,且x,y,z都不为0,求(3x*x+y*y+4z*z)/(5x*x+y*
已知x:y:z=2:3:4,且x-y+z=36,求x+y+z的值.
已知x:y:z=2:3:4,且x+y+z=18,求x,y,z的值
已知x/2=y/3=z/4,且x+y+z不等于0,求2x+3y-4z/x+y+z的值
已知x+y/2=y+z/3=z+x/4,且x+2y+z=12,求x-2y+z的值
已知4x-3y-6z=0,x+2y-7z=0,且x,y,z≠0,求2x+3y+6z/x+5y+5z的值.
已知3x=4y=5z,且x不等于0,求2x-3y+6z/3x-2y+4z=?
已知x:y:z=3:4:5,3x+2y-4z=18.求:x+y+z.
已知2x+5y+4z=6 3x+y-7z=-4求x+y-z
已知x/4=y/5=z/6 求x+y+z/3x-2y+z的值
已知x/4=y/5=z/6,求x+y+z/3x-2y+z的值.