A different way to notice that the right triangle is isosceles

In the video, we found that the triangle was a 454590 triangle. Since the angles touching the hypotenuse are the same (45 degrees each), the legs of the triangle are the same length. If someone could offer me a diagram, that would be great!

@professionalbronco Yeah that's exactly right! That's another good way to figure that out. Both the way you suggest and the line of symmetry that Prof. Loh drew are really clever solutions. Goes to show how many ways there are to look at the same thing
And here's the diagram that you requested:

@quacker88 thanks for the diagram! In the future, how can I post diagrams myself?

@professionalbronco I made mine using Google Drawings, and then I just downloaded it and pasted it here. It's really easy to paste images into posts, so as long as you can find a website to make the diagram that's all you'll need