I invested in a friend's start-up via a convertible note. The business ceased operations. How do I write off this investment? I recovered a portion of the original principle

I invested in a friend's start-up via a convertible note. The business has ceased operations and I am curious how to write off this investment. I recovered a portion of the original principal investment from a few years ago. The convert did not pay any cash interest over its life outstanding. 

 
The below seems similar but I want to make sure there is no difference since I had a 28% recovery.