@paulxthompson@cazmockett I think that can be simplified further but I need to write it down to check. Possibly something like R=H-(W²/4H). My approach and I guess the others is to use Pythagoras rather than angles.
This is hilarious. I am now so use to virtual keyboards that I found myself searching for the Ohm (omega) key on a laptop. Give me a week and I will be trying to zoom in on a piece of paper. 😅