Light It Up

I made this interactive for the NCTM Illuminations activity 'Light It Up' from Set the mirror position and laser height. Then collect data for how high the spot on the wall is (output) for how far from the wall you're standing (input) You can click on Trace to see the relationship. Can you find a function rule for this input/output?
Hint: the lesson suggests y =c+a/(x-b) for a rule form. Modified from the original made by John Golden