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...

This site gives an explanation of what the base of a polygon is. The base of a polygon when given the location of the altitude is also discussed.

This lesson will demonstrate how to locate the height in an obtuse, right, and acute triangle. It is 2 of 5 in the series titled "Triangle Height."

This lesson will demonstrate how to locate the height in an obtuse, right, and acute triangle. It is 4 of 5 in the series titled "Triangle Height."

[Free Registration/Login Required] Travel around the world to different locations and explore the relationship between altitude, vapor pressure, and boiling point.

Located in China, the Yangtze River is one of the longest rivers in the world, reaching a length of around 6300 kilometres (3917 miles). This high altitude photo of the Yangtze River shows where the Three Gorges Dam is located. For more...