CK-12 Foundation
Ck 12: Geometry: Lines and Angles Study Guide
This study guide on lines and angles covers key terminology; line notation; parallel, perpendicular, and skew lines; and postulates and theorems about lines. It is available for download with free registration.
CK-12 Foundation
Ck 12: Geometry: Angles and Transversals Study Guide
This study guide on angles and transversals covers key terms, angle types formed by transversals, postulates and theorems about transversals, and how to prove if lines are parallel or perpendicular. It is available for download with free...
CK-12 Foundation
Ck 12: Geometry: Lines in the Coordinate Plane Study Guide
This study guide on lines in a coordinate plane covers key terms, what different line slopes look like, postulates about parallel and perpendicular lines, the slope-intercept equation, how to graph parallel and perpendicular lines, and...
Wolfram Research
Wolfram Science World: Karl Friedrich Gauss (1777 1855)
A comprehensive summary of Gauss work, primarily mathematical. An incredible number of hotwords, along with many links to other scientist and mathematicians.
University of St. Andrews (UK)
University of St. Andrews: Johann Heinrich Lambert
This page, which is provided by the University of St Andrews, offers a short biography on Johann Heinrich Lambert, a French-German mathematician (1728-1777.) It discusses his life and his contributions to mathematics.