How do I locate and loosen the rear derailleur hanger bolt? Context:

I need to remove my rear derailleur so that I can attach an alignment tool and straighten things out.

Images of the rear derailleur while the bike is upside-down:


http://www.zooomr.com/z/photos/zoom/9626152/size-8/
http://www.zooomr.com/z/photos/zoom/9626153/size-8/


Question:

Where is the derailleur's hanger's bolt that attaches the derailleur to the frame?

Solution:


Find a hex wrench with a long handle (at least as long as the 3-way hex wrench from Park Tools)
Turn counter-clockwise in the area circled in red by Jerry.
I've put a red circle around the hanger bolt.