I’ve written a short post on the triangle inequality for altitudes. As usual, I put it over on the math blog I have with my company, just because the support for literally everything is much nicer.
But, in the off chance you want it, I have a PDF. I’ve played around with a wonderful program called Typora, which I’ve been using for a few months to write any blog posts when I’m not in my iPad. It has great Mathjax support (miles better than WordPress), and so it’s easy to switch between the blog I use and this program, and I can export cleanly to PDF, as well as EPub and other formats that are really difficult to work with if I were using straight up LaTeX.
TriangleInequalityforAltitudes