3x-4y-z=0 ......(1)2x+y-8z=0 ......(2)移项:3x-4y=z ......(3)2x+y=8z ......(4)(3)+(4)*4:11x=33zx=3z将x=3z代入(3)得:9z-4y=z4y=8zy=2z∴x/y = (3z)/(2z) = 3/2