If we look at point C, once again there is no point after C to specify it as a ray, we can have a ray CE, starts at C goes through E and goes on for ever, you can also have a ray starting at C, going through F and going on forever, CE &amp; CF are the same rays as F sits on ray CE and E sits of ray CF, so CE &amp; CF are the same rays, now lets think about what we can do from point E,