Why do I get different answers with different methods - Thevenin

[Yealtas]

Homework Statement

Determine the Thevenin equivalent of the following circuit:
https://imgur.com/a/74UjA (Top image)

Homework Equations

-

The Attempt at a Solution

The last 3 images in the Imgur album are all different approaches.

I can't figure out what the right one is, and why the other ones are wrong. I spent hours searching on google, and I feel like I understand Thevenin/Norton well -now I am not so sure..-, but to no avail.

Extra information:
- Ub = Usource
- "zal door Rv gaan" means "will pas through Rv"

EDIT: I think my second attempt is correct. Uth = 5V. The 1st and 3rd method are presumambly wrong. I sort of have an idea of why, but I am still not 100% convinced.

 

[CWatters]

Can you write down the steps you are taking eg...

1) Remove load resistors (none to remove in this case)
2) Replace current sources with..

etc

 

[gneill]

Hi Yealtas,

Please upload your images and embed them in your posts as local attachments. You can use the UPLOAD button at the bottom right of the edit window.

We find that off-site stored images and documents have a tendency to "evaporate" over time, rendering their threads here nearly worthless to members who come across them in the future.

Thanks.

 

[CWatters]

EDIT: I think my second attempt is correct. Uth = 5V.

Yes and Rth = 5500 Ohms.

Re: First image/attempt: You appear to be shorting the output to calculate I₅ when you should be calculating the open circuit voltage (so I5 = 0).