This article was originally published with the title “ Non-Euclidean Geometry before Euclid ” in Scientific American Magazine Vol. 221 No. 5 (November 1969), p. 87 doi:10.1038 ...

This course is designed for current and prospective geometry teachers. In addition to the development of Euclidean geometry, students will become familiar with geometry applications in Geometer's ...

Narrator: What’s important to understand is that geometry has rules, has facts you need to know. Here’s a rule you probably know: that a shape with 4 right angles and 4 equal sides is a square!