This is a fun problem given from Sadiku's Fundamentals of Electric Circuits text. The chapter covering supernodes gives a good explanation of how to use and solve circuits that would govern the use of a supernode. However, it fails to introduce how to solve a circuit that involves a supernode using more than two nodes. This is the circuit pictured below. I have gone about this in more than one way. My latest attempt came very close at the books given answer however was still not correct. Using nodal analysis determine the three voltages. Any help is greatly appreciated.