by James King, University of Washington

These pages were constructed with Geometer's Sketchpad 4 (see below). They are not organized at the moment, and the topics are quite miscellaneous. Perhaps more sketches and better organization will follow in time. Any links to the individual pages may change in the future.

**Euclidean and/or Affine Plane Geometry**

- Two Centers of Mass of a Quadrilateral
- Affine Transformation of a Quadrilateral
- Affine Image of a Circle is an Ellipse
- Parallel Projection of a Parallelogram
- Affine Coordinates on a Line and on the Plane
- An Example of Barycentric Coordinates and Triangle Area

**Projective Geometry**

**Poincare Model**

**Polyhedra**

**Spherical Geometry via Stereographic Projection**

**Euclidean Plane**

These pages use **JavaSketchpad**,
a World-Wide-Web component of *The
Geometer's Sketchpad.* Copyright © 1990-2001 by KCP Technologies,
Inc. Licensed only for non-commercial use.