Angles of a Triangle

For studying the triangles in geometry, we have to learn the angles formed in a triangle.

Interior angles

An angle formed by the intersection of any two sides of a triangle at a vertex is called an interior angle of a triangle. In a triangle, three sides are intersected at three non-linear points. Thus, the three sides form three angles internally at three vertices.

Now, learn the formation of interior angles of a triangle from an understandable animation and also learn the geometrical property of internal angles of a triangle.

Exterior angles

An angle made by a side and an extended adjacent side of a triangle is called an exterior angle of a triangle.

In a triangle, three sides can be extended in six different directions at three vertices. Thus, the three sides form six angles externally at three vertices.

Now, learn how the external angles are formed in a triangle from an understandable graphical animation.