Altitudes of Triangles and Orthocenter

I introduce altitudes in triangles and point of concurrency, the orthocenter. I finish by working through two examples, the last of which finding the orthocenter given the three vertices of a triangle. EXAMPLES AT 7:10 10:31 Find free review test, useful notes and more at http://www.mathplane.com/ If you'd like to make a donation to support my efforts look for the "Tip the Teacher" button on my channel's homepage    / profrobbob