Please click the image to enlarge it http://img237.imageshack.us/img237/3605/untitlednu9.th.jpg [Broken] I'm having trouble seeing how this circuit was reduced. Can anyone shed some light on it for me? My question pertains to the second solution in the image. I see that the 12k and 4k resistors are in parallel and that leads to the second diagram on the bottom. Why is the 6k resistor drawn up there? When I try to redraw the circuit, I keep it just like the first one- with the exception that the 12k and 4k resistors are combined on the rightmost branch- with the 6k and the current source in the same place. When the 6V source is shorted out why is there a need to redraw that branch?