[Free Registration/Login Required] Students will use the interactive riangle and points to explore altitudes such as the orthocenter. Click learn more to watch a video and click challenge me to answer a practice question.

[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.

This study guide on bisectors, medians, and altitudes covers key vocabulary, different theorems, and facts about the altitude and triangles. It is available for download with free registration.

This site from InterMath gives a description of the orthocenter of a triangle along with a visual representation. Be sure to follow the links to related terms, everyday examples, challenging problems, more information, and the...

In this activity, students use the Cabri Jr. tools to draw altitudes in a triangle. They construct a line perpendicular to a given line and through a given point. [Requires Adobe Reader.]

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

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...

This site defines the altitude of a triangle and gives the standard notation for altitudes of a triangle. The site then goes to list several proofs involving altitudes and orthocenters.

Students understand that the orthocenter is the point of concurrence of the three altitudes of a triangle. They construct circumcircles and Feuerbach circles and determine the relationship between them.

Learn about the orthocenter 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.

This site describes altitudes and orthocenters in triangles and their connections with the nine-point circle.

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

You will find an interactive activity to review the following concepts: altitude, median, angle bisector and points of concurrency in triangles. Five different interactive quizzes are also provided to test your knowledge.

Learn how to construct the bisectors, median and altitude of a triangle.

This site describes altitudes and orthocenters in triangles and their connections with the nine-point circle.

This site describes altitudes and orthocenters in triangles and their connections with the nine-point circle.

This site describes altitudes and orthocenters in triangles and their connections with the nine-point circle.

This site describes altitudes and orthocenters in triangles and their connections with the nine-point circle.

This site describes altitudes and orthocenters in triangles and their connections with the nine-point circle.

This site describes altitudes and orthocenters in triangles and their connections with the nine-point circle.

This site describes altitudes and orthocenters in triangles and their connections with the nine-point circle.

This site describes altitudes and orthocenters in triangles and their connections with the nine-point circle.

This site describes altitudes and orthocenters in triangles and their connections with the nine-point circle.

This site describes altitudes and orthocenters in triangles and their connections with the nine-point circle.