Paul Lockart paper shows Not Found, so here’s an Internet Archive link: https://web.archive.org/web/20170514160142/https://maa.org/external_archive/devlin/Lock

Paul Lockart paper shows Not Found, so here’s an Internet Archive link: https://web.archive.org/web/20170514160142/https://maa.org/external_archive/devlin/LockhartsLament.pdf https://web.archive.org/web/20170514160142/https://maa.org/e... The paper shows a dotted line dividing the triangles and showing the areas to be equal, which makes things clearer.