已知3x-4y=07x=4z,则x+y+zx= ___ .
已知x+2y-3z=0,2x+3y+5z=0,则x+y+zx-y+z= ___ .
已知3x=4y=5z,x≠0,则2x−6y+5zx−4y+5z
已知三个数x,y,z.满足xy/x十y=一2,yz/y十z=4/3,zx/z十x=一4/3则xyz/xy十yz十zx的值
已知三个数x,y,z,满足xy/x+y=-2,yz/y+z=4/3,zx/z+x=-4/3,求(xyz)/(xy+yz+
实数x、y、z满足x+y+z=5,xy+yz+zx=3,则z的最大值是 ___ .
已知{3x-4y-z=0 求x^2+y^2+z^2/xy+yz+2zx的值 2x+y-8=0
已知x-y=4,y-z=2,求x^2y+y^2z+z^2x-(xy^2+yz^2+zx^2)的值
已知x-y=4,y-z=2,求x^2y+y^2z+z^2x-(xy^2+yz^2+zx^2)的值.
1.已知4(xy-zx-y²+yz)=-z²+2zx-x²,求z-zy+x-3的值
已知xy:yz:zx=3:2:1,求①x:y:z ②x/yz:y/zx
已知x/3=y/4=z/2≠0则2x^-2y^2+5z^2/xy+yz+zx
已知三个数x,y,z满足xy/x+y=-2,yz/y+z=4/3,zx/z+x=-4/3,求xyz/xy+yz+zx的值