I. \( x+y+z=3 \)
II. \( 2 x+y-2 z=1 \) | -2* 1.Gl.
III. \( 2 x-2 y+3 z=3 \) | -2* 1.Gl.
==>
I. \( x+y+z=3 \)
II. \( -y-4z=-5 \)
III. \( -4y+z=-3 \) | -4* 2. Gl
==>
I. \( x+y+z=3 \)
II. \( -y-4z=-5 \)
III. \( 17z=17 \)
==> z=1 und -y-4=-5 ==> y=1
und x+1+1=3 also auch x=1 .