Simple geometric theorems by origami Origami geometry examples are collected here. The programs run on Eos3.3.2. centroid.nb Ceva’s Theorem.nb circumcenter.nb EulerLine.nb excenter.nb Incenter.nb Menelaus’s Theorem.nb nine-point-circle.nb orthocenter.nb Simson Theorem.nb Steiner-Lehmus Theorem.nb