Learn about the circumcenter of a triangle with this handy reference guide. Provides a detailed definition, examples, and an interactive activity that enhances further explanation. Includes links to related topics.

Here at The Math Forum, Dr. Math offers interesting properties of orthocenters. Links are provided at the bottom of the page for information on associated topics.

In this activity, students examine the location of the circumcenter and incenter for different triangles.

[Free Registration/Login may be required to access all resource tools.] This concept teaches students properties of angle bisectors and how to apply them.

[Free Registration/Login may be required to access all resource tools.] This concept teaches students the properties of medians and how to apply them.

Based off of the hit television show NUMB3RS, this lesson introduces students to Voronoi diagrams, which split a plane into regions corresponding to distances to given points. The lesson is framed in the context of splitting a city into...

This site from MathWorld gives a diagram of a triangle with its centroid labeled. The site details how to find the centroid with links to the key terms. The site details many other interesting properties of the triangle centroid.

MathWorld diagrams triangle with its incenter labeled and details how to find the incenter with links to the key terms. The site details many other interesting properties of the triangle incenter.

A labeled illustration of an incenter inside a triangle.

[Free Registration/Login may be required to access all resource tools.] Apply the fact that the altitude of a right triangle creates similar triangles.

[Free Registration/Login may be required to access all resource tools.] This concept teaches students properties of altitudes of triangles and how to apply them.

In Spanish. Interactive activities dealing with the concept of angle bisector, median and altitude of a triangle. A description of the circumcenter and centroid are given along with a visual representation. [Requires Java.]

A complete reference guide to points, lines, and planes. It provides definitions and interactive activities that enhance further explanation.

Here at the Math Forum, Dr. Math proves the concurrency of the altitudes of a triangle. Links are provided for associated topics.

Dr. Math shows how to construct the orthocenter of any triangle using a compass and straight edge.

This site from MathWorld provides a diagram of a triangle with its orthocenter labeled. The site details how to find the orthocenter with links to the key terms. The site details many other interesting properties of the triangle...

At this page you will find Dr. Math responding to an inquiry about the relevance of the names of each of the special triangle centers.

[Free Registration/Login may be required to access all resource tools.] This concept teaches students how to construct perpendicular bisectors and use the Perpendicular Bisector Theorem.

You will need to do some visualizing to solve this "Right Time" problem. Have fun!

[Free Registration/Login may be required to access all resource tools.] Apply the fact that an angle bisector divides a triangle proportionally.

[Free Registration/Login may be required to access all resource tools.] This concept teaches students how to set up and solve proportions with angle bisectors.

[Free Registration/Login may be required to access all resource tools.] Apply perpendicular bisector properties.

[Free Registration/Login may be required to access all resource tools.] Apply the Median Theorem.

In this activity, using the USA TODAY Snapshot "Dangerous births" students will explore the geometric relationships of triangles using perpendicular bisectors of the sides, bisectors of the angles and medians of the triangle. They will...