An altitude is a segment that goes from the vertex to the opposite side and forms a right angle with that side. Drag the vertices of the triangle below to explore the altitude.
All three altitudes meet at a point. The point of concurrency for the altitudes is called the orthocenter. Can the orthocenter be outside the triangle? If so, when?
Move the vertices so the triangle is a right triangle. Where is the orthocenter?
On the vertex of the right angle
There is no special property of orthocenter.