Khan Academy Static

Roughly 2400 years ago, Euclid of Alexandria wrote Elements which served as the world's geometry textbook until recently. Studied by Abraham Lincoln in order to sharpen his mind and truly appreciate mathematical deduction, it is still the basis of what we consider a first year course in geometry. This tutorial gives a bit of this background and then lays the conceptual foundation of points, lines, circles and planes that we will use as we journey through the world of Euclid.

4164_Geometric_definitions_example.html

4161_Terms_labels_in_geometry.html

4160_Euclid_as_the_father_of_geometry.html

4163_Specifying_planes_in_three_dimensions.html

4162_Lines_line_segments_rays.html