The angle of the various points is letter A. When you look at the illustration, and you can already see a clue of what the possible angle is going to be. The edge on the other side measures 52 Degrees. It only follows that a different perspective will also be the same. Do you know that measuring angles has always been a problem of people, even those who are from ancient times?
They have used different ways to measure angles because they find this important, especially if they are working on something that would need precision. Angles are used in our daily lives, and they are always here to be measured and to ensure that everything will go accordingly.