This procedure is tedious, but it requires very little fancy math and it's conceptually beautiful. You ought to be able to look at the finished product and explain WHY the values of voltage drops and currents for each resistor and combination of resistors have the relationships they do. Yay! You can now simplify any circuit with just one battery and a bunch of resistors...or can you? Those in the know call this finding the Thevenin Equivalent circuit, 'cause the method was proven by Thevenin long ago.

Want more? This is part of a larger playlist on circuits:    • AP Ch 21 - Circuits  

I have actually made a bunch of physics videos. Feel free to find my other playlists if you're lonely on a Saturday night. Or if you just want to know stuff so you can begin your takeover.