Thevenin's Theorem and Norton's Theorem

[picogenkaku]

Hi guys, I'm stuck with determining how will I solve this circuit using Thevenin's and Norton's Theorem.

Given Problem: From the circuit (which is in the image), find the voltage across a 6-ohm resistor using Thevenin's Theorem and Norton's Theorem.

The attempt at a solution

Using KVL on the four loops, I will get:

7I_a - 6I_b = 12 ---- Equation 1
13I_b - 3I_c = 3 ---- Equation 2
-15I_c + 7I_d = 3 ---- Equation 3
7I_c - 9I_d = 9 ---- Equation 4

and here I don't know what's next.

Our professor gave this problem without teaching the principles of Thevenin and Norton's Theorem. So a short discussion while solving the problem is much appreciated. Thank you. ^^

 

[vela]

Start by reading your textbook about Thevenin and Norton equivalents. If you don't have a textbook, Wikipedia has a decent summary of them. Describe to us what the theorems say you can do. (Don't get too bogged down in how to find them. I just want you to get the idea of what you're trying to do.)