Geometric Constructions
Videos and lessons with examples and solutions to help High School students
learn how to make formal geometric constructions with a variety of tools and methods
(compass and straightedge, string, reflective devices, paper folding, dynamic geometric
software, etc.).
Lessons here include:
Copying a segment; copying an angle; bisecting a segment;
bisecting an angle; constructing perpendicular lines, including
the perpendicular bisector of a line segment; and constructing a
line parallel to a given line through a point not on the line.
Common Core: HSG-CO.D.12
Basic Geometric Constructions - copying line segments, angles and triangles
How to copy line segments, angles and triangles using a compass and a straight edge.
Bisecting an Angle
How to bisect an angle using a compass and a straight edge.
Constructing a Perpendicular Bisector of a Line Segment
How to construct a perpendicular line bisector using a compass and a straight edge.
Constructing a Line Parallel to a Given Point
How to construct a parallel line through a given point by using a straight edge and a compass.
Bisecting an Angle Efficiently
It is well-known that an angle can be bisected in the traditional way by drawing three arcs. However, it is possible to bisect an angle by drawing two arcs and two lines instead. This Demonstration shows one such method. Two concentric circles are constructed, centered on the angle to be bisected. The intersection of the two lines shown produces the desired bisection.
Bisecting an Angle Efficiently from the Wolfram Demonstrations Project by Nick James
Bisection of Line Segment
Bisect a line segment with compass and straight edge.
Bisection of Line Segment from the Wolfram
Demonstrations Project by Michael Schreiber
Patty Paper - Angle Bisectors
How to fold an angle bisector in a triangle using Patty Paper.
Patty Paper - Perpendicular Bisector
How to fold a midpoint or a perpendicular bisector using Patty Paper
Try the free Mathway calculator and
problem solver below to practice various math topics. Try the given examples, or type in your own
problem and check your answer with the step-by-step explanations.
We welcome your feedback, comments and questions about this site or page. Please submit your feedback or enquiries via our Feedback page.