已知3x=4y=5z,x≠0,则2x−6y+5zx−4y+5z
已知3x=4y=5z,x≠0,则2x−6y+5zx−4y+5z
已知x+2y-3z=0,2x+3y+5z=0,则x+y+zx-y+z= ___ .
(x-3y+z)^2+/ 5x-4y+z/=0 且xyz≠0 xy+yz+zx/x^2+y^2+z^2
已知x/3=y/4=z/2≠0则2x^-2y^2+5z^2/xy+yz+zx
已知方程组4x-5y+2z=0 x+2y=3z 则x:y:z
已知2x-3y-z=0,x+3y-14z=0,且x,y,z不全为0,求4x的平方-5xy+z的平方/xy+yz+zx的值
已知4x-3y-6z=0,x+2y-7z=0,且x,y,z≠0,求2x+3y+6z/x+5y+5z的值.
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2x+5y+4z=6 3x+y-7z=-4求x+y-z
已知2x+5y+4z=15.7x+y+3z=14 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.