x+y+z=17 2x-y-2z=1 3x+y-4z=3怎麼解

x+y+z=17 2x-y-2z=1 3x+y-4z=3怎麼解

x+y+z=17 2x-y-2z=1 3x+y-4z=3
x= 8,y= 3,z= 6