Published Online: Aug 31, 2016
Page range: 27 - 36
Received: Dec 30, 2015
DOI: https://doi.org/10.1515/forma-2016-0003
Keywords
© by Roland Coghetto
This work is licensed under the Creative Commons Attribution-ShareAlike 3.0 License.
We introduce the altitudes of a triangle (the cevians perpendicular to the opposite sides). Using the generalized Ceva’s Theorem, we prove the existence and uniqueness of the orthocenter of a triangle [7]. Finally, we formalize in Mizar [1] some formulas [2] to calculate distance using triangulation.