已知x/3=y/4=z/2≠0则2x^-2y^2+5z^2/xy+yz+zx

已知2x-y-z=0,3x+4y-2z=0,则x：y：z=? 已知x-2y+3z=0,x-3y+4z=0,则x:y:z= 已知{x-3y+2z=0 3x-3y-4z+0,则x:y:z=? 已知x+4y-3z=0,4x-5y+2z=0,则x：y：z 已知方程组4x-5y+2z=0 x+2y=3z 则x:y:z 已知3x-4y-z=0,2x+y-8z=0,且z≠0,则x：y：z=（ ） 已知：4x-5y+2z=0 x+4y-3z=0则：(x*x+y*y+z*z)/(x*y+y*z+z*x)=____. 已知x+2y-4z=0,3x-y-z=0,则3x+2y+z/x+2y+z= 已知4x-3y-6z=0,x+2y-7z=0,则x-y+z/x+y+z=_________ 已知4x-3y+6z=0 x+2y-7z=0 则x-y+z/x+y-z=? 已知{4x-3y-6z=0、x+2y-7z=0,则x-y+z：x+y+z= 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,方程组:4x-3y-7z=0 x+2y=10z 则(x-y+z)÷(x+y+z)=—— 三元一次方程组题目x+y-z=11 y+z-x=5 x-y+z=1x+y=4 y+z=3 x+z=5若已知x-3y+2z=0 2x+3y-8z=0, 且xyz≠0,则x:y:z= 已知方程组4x-3y-2z=0,x-3y+z=0,z≠0求x/z,y/z的值 已知方程组2x-3y-4z=0和x+y+z=0,并且z≠0,求x：y与y：z 已知x+4y-3z=0；4x-5y+2z=0,则3y-5z分之2x-y+3z=? 已知{x+4y-3z=0,4x-5y+2z=0,则2x-y+3z分之3y-5z=?