Stewart's Theorem: Proof and an Example

In this edition of Awesomeness...we demonstrate a proof of Stewart's Theorem. Discuss it's usefulness, and ultimately give an example of it's application on a test. Also I mention the example is from 2021 AMC 10 and AMC 12 tests, and this was a bad memory on display. I knew I had used it recently, but it wasn't on those tests. Sad day. The actual example is from 2002 AMC 12B

This video is done by request from A YouTube User I will name if they respond back to my email. I have decided not to automatically name people who send me Problem Requests as some people want privacy, and some people would love a shout out. I will likely change the Problem Request Form to allow input of whether you want your Username mentioned or not.