Thevenin's Theorem - Dependent Source + Resistor

[verd]

Hey,

I'm having a bit of difficulty with this one. I spoke to my professor specifically about this problem, he worked through it, I understood him, and I worked through it later in the day. I still get it, I worked through it, and there's step at the end that we both did differently. It seems like a simple KCL thing, but here's the problem:

Find the Thevenin equivalent of the network in the figure at the terminals A-B.
http://synthdriven.com/images/deletable/EEN201-06.jpg This is what I did:
http://synthdriven.com/images/deletable/EEN201-07.jpg

Now, what we did differently was what I circled as step six. Focusing on Node 2. It was finding the incoming current from point A. I just used KCL because I had the two other currents, and that's what it looks like my professor did.

However, he somehow gets 3Ix as an answer for Isc, which would give him a final answer of 333ohms.

What exactly did he do? Or is he the one making the error??

I get (5/2)Ix for Isc, which gives me 400ohms as a final answer.Thanks!

 

[doodle]

Your solution looks good to me.