geometry puzzle

[cellio]

You're being too productive; let me help:

World's hardest easy geometry problem, forwarded by a coworker, allegedly solvable with pure geometry (no trigonometry).

Comments

[caryabend.livejournal.com]

multi-variable system of equations

I'm pretty sure that's not elementary geometry.

[cellio]

I wasn't sure if that was a legitimate approach (algebra came before geometry in my education), but I didn't go down that path because of the claim of "here is everything you need to know to solve this" farther down on the page (which doesn't mention equation-solving).