The median of a triangle is the segment that joins a vertex of a triangle to the midpoint of the opposite side. Every triangle has 3 medians. The medians of a triangle meet in one point which is called the centroid of the triangle. It is also the center of mass. The medians of a triangle always meet inside of the triangle.
Concurrent lines are lines that meet in exactly one point.
The medians of a triangle are concurrent lines. Altitudes of triangles the altitude of a triangle is the segment drawn from a vertex perpendicular to the line containing the opposite side. An altitude is sometimes referred to as the height of the triangle. The three altitudes of a triangle are concurrent and meet at a point that is referred to as the orthocenter . Auxiliary lines extra lines added in a diagram to aid in the solution of a proof.