Ceva's Triangle Theorem
Ceva's Triangle Theorem
A Cevian is any segment from a vertex of a triangle to a point on the opposite side.
Three concurrent Cevians divide the three sides into pairs of segments.
The product of the ratios of these segments, where the ratios are taken in the
same orientation on each side, is equal to 1.
https://en.wikipedia.org/wiki/Ceva's-theorem