Dictionary
search :       browse : 
A B C D E F G H I J K L M
  N O P Q R S T U V W X Y Z
         
Description
Related Terms
Everyday Examples
Interactive Checkpoint
More Information
Challenge
How to use this dictionary
Contact
 Description  
 Altitude of a Triangle:  The perpendicular distance between a vertex of a triangle and the side opposite that vertex. Sometimes called the height of a triangle. Also, sometimes the line segment itself is referred to as the altitude.
Note that since there are 3 vertices in every triangle, there are also 3 altitudes in every triangle! The altitude of the triangle depends on the vertex and the opposite side (or base) you are using.
Examples of Altitudes


The altitude (h) of this triangle is shown in red.

You can find the altitude or the height of a figure by measuring the segment (h) that is perpendicular to the base and that meets the opposite vertex (E). This segment h can also be called the altitude.



Sometimes the altitude will fall outside the figure, as in the triangle to the right. In this case, you need to extend the base of the figure so that it intersects the altitude at a right angle.

Non-Example of Altitude


In this picture, the green segment is not an altitude of the triangle since it is not perpedicular to a base (BC) of the triangle. The altitude is indicated in red.