© 2016 Shmoop University, Inc. All rights reserved.

At a Glance - Three-Sided Shapes

We call a three-sided shape a triangle You know these guys; they have been made famous thanks to pizza.

The perimeter of a triangle is the sum of its three sides. The area A of a triangle is given by the formula


This formula is the way it is because the triangle fills exactly half of a rectangle with side lengths b and h, as shown below.


People who Shmooped this also Shmooped...