1. The problem statement, all variables and given/known data I really don't see how the Thevenin equivalent circuit is obtained from the one on the left. The way learnt to find Thevenin equivalent circuit considers the circuit network in between 2 nodes. This one appears to have 3 nodes. And why is the thevenin resistance given as though the resistance were connected in parallel? I don't see why they are in parallel. 2. Relevant equations/pictures Thevenin equivalence.