Videos of Geometric Constructions

The videos here are meant to help beginners with basic geometric constructions and some example applications. It is recommended that you go at your own pace, pausing the videos to try what you see and replaying parts that you're unsure about. I hope you find these useful!

If you're interested in using the constructions applet I developed (which is used in these videos), visit here: http://feromax.com/compass/.

Remember to watch videos in fullscreen mode at high resolution (720p HD)!

1. Copy a Line Segment (Construction #1)
   • construct segment 3x's as long as a given segment
   • construct an equilateral triangle (how to make 60-degree angles)
   • copy a triangle (SSS method)
     
     
2. Copy an Angle (Construction #2)
   • construct an angle twice the size of a given angle
   • construct a 120-degree angle
   • copy a triangle (SAS method)
     
     
3. Construct a Perpendicular Bisector of a Segment (Construction #3)
   • find midpoint of a segment & splitting a segment into quarters
   • construct an isosceles triangle
   • construct a median in a triangle
     
     
4. Construct a Perpendicular Through a Point Not on a Given Line (Construction #4)
   • construct an altitude in a triangle
     
     
5. Bisect a Given Angle (Construction #5)
   • construct a 30-degree angle
   • construct a 45-degree angle
     
     
6. Construct a Line || to a Given Line via Corresponding Angles (Construction #6)
   • alternate method for || lines
     
     
7. Miscellaneous
   • construct a rhombus
   • construct a square
   • construct an isosceles right triangle

All videos linked to this page are ©2012 by Michael Ferraro.