已知x/3=y/4=z/5,则(x+4y+2z)/(8x+y+6z)=
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.
已知2x+5y+4z=15.7x+y+3z=14 则x+y+z=?
已知x+y=3,y+z=4,x+z=5,则x+y+z等于( )
已知2x+5y+4z=6 3x+y-7z=-4求x+y-z
已知方程组4x-5y+2z=0 x+2y=3z 则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.
已知2x+3y-4z=0,3x+4y+5z=0,求x+y+z/(除以)x-y+z的值.
已知方程组4x-y+3z=0 2x+y+6z=0且xyz不等于0,则x/y+y/z+z/x是多少
已知3X=4X,5Y=6Z求X+Y:Y+Z
已知3x=4Y,5Y=6Z,求 (1)x:y:z;(2)x+y/y+z.
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*