### Home > INT2 > Chapter 9 > Lesson 9.3.1 > Problem 9-89

9-89.

The United State Department of Defense is located in a building called the Pentagon because it is in the shape of a regular pentagon. Known as “the largest office building in the world,” its exterior edges measure

What is the area of land enclosed by the outer walls of the Pentagon building?

If 1 mile is equal to

feet, what is that area in square miles?

Find the area using trigonometric ratios.

The interior angles of a regular pentagon measure