Nimetön työkirja
Theorem 2.4.1. In a triangle, the sum of the measures of the interior angles is 180
We are now shoving that the sum of the measures of the interior angles of all triangles is 180[math]^\circ[/math]. First we will show some examples of this statement and in the end we provide a formal proof for this theorem.
1. Example triangle ABC
2. Example triangle DEF
Proof of the theorem
Now we will make a formal proof so that we can see these two example triangles are not only exceptions but that the theorem 2.4.1. is always valid.