已知3x=4y,3y=4x,求x:y:z
已知3X=4X,5Y=6Z求X+Y:Y+Z
已知5x=3y,4z=7y,求x:y:z
已知3x=4y,2y=5z,试求x:y:z
已知3x=4y,3y=4x,求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-
已知x/2=y/3=z/4,求下列各式 (1)(x+y+z)/x (2)(x-y+2x/(x-y-2z)
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3X+7Y+Z=6 4X+10Y+z=7 求X+Y+Z=?
已知x/3=y/4=z/2,求x+2y-z/x+y+z=?
已知x:y:z=2:3:4,且x-y+z=36,求x+y+z的值.
已知2x=3y=4z求2x-y+z分之x+y+z的值