若x:y:z=2:3:4
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x/2=y/3=z/4不等于0,求x+y+z/x+y-z的值
已知x::y:z=3:4:5,(1)求x+y分之z的值;(2)若x+y+z=6,求x,y,z.
若x-2y+4z=1,x+3y-7z=0,则y:z=?
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
x=y/z=z/3,x+y+z =12,求2x+3y+4z是多少,
已知x/2=y/4=z/7,求①x:y:z.②若2x+y+3z=58,分别求x,y,z的值.③求x+y/x+z的值.
若X:Y:Z=2:3:4求X+Y+Z/X-2Y+3X的值
已知x:y:z=2:3:4,求x-y-z/3x+2y-z的值.若2x+3y-4z=-3,求3x-4y-z的值
已知2x+3y-4z=7 3x-2y+z=3 x+5y+9z=20 则 x+y+z= 若x :y :z=2 :3 :7
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