Exterior of a triangle is an area which lies outside the boundaries of a triangle.
Or In order words,
Exterior of a triangle is an area which lies outside the three sides of a triangle.
Or we can also say that;
An area outside the boundaries or perimeter of a triangle is known as exterior of a triangle
Example 1: In the below diagram:
Entire area highlighted in green is referred to as Exterior of triangle ABC.
Example 2: In the below diagram:
Points P, Q, R, S & T lies in the exterior of triangle ABC.
