Välisnurgade

Välisnurgade, also known as external angles, are the angles formed outside the sides of a triangle when the sides are extended. These angles are supplementary to the internal angles of the triangle, meaning that the sum of an external angle and its adjacent internal angle is always 180 degrees. There are three external angles in any triangle, one at each vertex.

The study of external angles is a fundamental topic in Euclidean geometry, which deals with the properties and relationships of points, lines, surfaces, and solids. External angles are often used in geometric proofs and calculations, such as finding the measure of an unknown angle or determining the congruence of triangles.

In practical applications, external angles can be used to solve real-world problems, such as calculating the angles of elevation or depression in surveying and navigation. They are also used in fields like architecture and engineering to design structures with specific angle requirements.

Understanding external angles is essential for a comprehensive grasp of geometric principles and their applications in various fields.