My textbook says that these two circuits are equivalent. The first is not easily solvable, the second is. I have looked around the site at a number of questions and this situation is not addressed anywhere, the answers mostly revert you to using Kirchhoff's laws. My textbook says that this circuit can be solved through series/parallel relationships. Of the two equivalent circuits in the image, what is the general method (for solvable cases, don't revert to other methods) for getting from the first to the second?
It is solved by combining 3,5 in series, that with 4 in parallel, all of that with 2 in series, and putting all of that in one resistance in parallel with 6,7,8. What is the logic here if you were confronted with just the first diagram?