Interior angles in a triangle add up to 180˚. Triangles close triangleA polygon with three straight sides. have three sides, therefore they have three angles. Interior angles in a triangle sum to a ...

The class Geometry: Triangles discusses triangles and the specific mathematical operations unique to them. While the triangle is a very basic shape, it can be found as a part of more complex shapes.

Everyone learns the number one rule about triangles in high school: the angles of a triangle add up to 180 degrees. But did you know that sometimes they don't? Triangles are much more interesting than ...