Texas Instruments
Texas Instruments: Angles Formed by Two Intersecting Lines
Students will investigate the properties of angles formed by intersecting lines. They examine the definition of adjacent angles, supplementary angles, and vertical angles and learn about two important geometric theorems dealing with...
University of Cambridge
University of Cambridge: Nrich: Logo Programming Overlapping Polygons
Using this Logo Program you can experiment with different values for N in the procedure and see the changes in the results.