
 Assignment2 
  The orthocenter (H) of a triangle is the intersection of the three lines containing the altitudes. 
  The figure below is a construction using Geometer's Sketchpad of a triangle with the three midpoints of the sides, the altitudes, the feet of the altitudes, the orthocenter H, and the three midpoints of the segments from the respective vertices to the orthocenter. 
  Notice that, with a right triangle, the orthocenter, two of the feet of the altitudes, and the midpoint between the orthocenter and the vertex of the right angle are concurrent with the vertex of the right angle. 
 web.pdx.edu /~pconnor/Assignment2.html (780 words) 
