http://mathforum.org/kb List of forum topics en http://mathforum.org/kb/thread.jspa?messageID=1084285&tstart=0#1084285 Try going to mathforum.com and check out their Ask Dr. Math section.
This question has been asked before and they have lots of good]]> Apr 4, 2000 11:21:47 AM Apr 4, 2000 11:21:47 AM art@mabbott.org 0 http://mathforum.org/kb/thread.jspa?messageID=1084284&tstart=0#1084284 properties of orthocenters. I love to prove her wrong and would love
to know all]]> Apr 4, 2000 8:04:13 AM Apr 4, 2000 8:04:13 AM kasmith15@hotmail.com 1 http://mathforum.org/kb/thread.jspa?messageID=1084283&tstart=0#1084283 4 major centers, it is the only one not mentioned in Euclid.

One]]> Dec 28, 1997 3:26:24 AM Dec 28, 1997 3:26:24 AM mkeyton@tenet.edu 2 http://mathforum.org/kb/thread.jspa?messageID=1084282&tstart=0#1084282 sides will lie on the circumcircle of the triangle. Are there any
other]]> Dec 27, 1997 8:29:45 AM Dec 27, 1997 8:29:45 AM ho@eagles.bbs.net.au 3