Ceva's Theorem If three Cevian lines are concurrent in a triangle, then there exists a special relationship between the ratios of the segments found on each side of the triangle.
Note: A line passing through a vertex of a triangle, but not coinciding with a side of the triangle, will be called a cevian line of the triangle for this vertex. A cevian line will be identified by the vertex to which it belongs and the point in which it cuts the opposite side, as cevian line AD through vertex A of triangle ABC and cutting the opposite side BC in the point D.
