已知x:y=3:5,y:z=2:3,则x+y+z2x-y+z的值为 ___ .
已知x:2=y:3=z:0.5,则x+3y−z2x−y+z的值是( )
已知xyz不等于0,x+3y+z=0,2x+3y-z=0,则x+2y-7z / 3x+5y+z的值为___?
已知x+2y-3z=0,2x+3y+5z=0,则x+y+zx-y+z= ___ .
已知x、y、z满足2x+3y+z=48 x-2y+2z=56 3x+5y+3z=52 则x+y+z的值为多少 急
已知2x+5y+4z=15,7x+y+3z=14,则4x+y+2z的值为______.
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x+y-z=0,2x-y+2z=0 求(3x-2y+5z)/(5x-3y+2z)的值
已知x+4y+3z=3x-2y-5z=0,求x+2y-z/2x-3y+7z的值
已知x,y,z,同时满足方程x+3y-5z=0,2x-y-3z=0求x:y:z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.