Wolfram Research
Wolfram Math World: Geometry
This MathWorld tutorial provides detailed overviews of the concepts and theorems associated with geometry. Most of the Math World sites are extensive and some require higher math knowledge to understand, links to terms and topics are...
University of Saskatchewan (Canada)
University of Saskatchewan: Geometry
The University of Saskatchewan's Department of Mathematics and Statistics provides high school students with online tutorials and exercises on what they deem some of the most important topics in geometry: Triangles, and Circles and Other...
Math Open Reference
Math Open Reference: Plane Geometry: Transformations
Explore transformations of a polygon that include: 1) translation 2) rotation 3) reflection and 4) dilation.
Other
The Mathematical Elements of Euclid
An extensive discussion of the Elements, which contains all the geometrical knowledge available in the Hellenistic period.
Varsity Tutors
Varsity Tutors: Hotmath: Practice Problems: Geometry in the Plane
Twenty-four problems presented on a variety of Plane Geometry topics. They are given with each step to the solution cleverly revealed one at a time. You can work each step of the problem then click the "View Solution" button to check...
Math Is Fun
Math Is Fun: Geometry
Students learn about geometry by investigating different shapes and their properties. Topics include plane geometry, drafting tools, transformations, angles, and trigonometry.