Learn at Mathematics Realm

This is the second part of the proof that the sum of the measures of the angles of a triangle is 180 degrees. This is actually the second method. The first one is more on using manipulatives or visual representations. This time, let us use basic.

Everybody knows that the sum of the measures of the angles of any triangle is 180 degrees. If I may ask each one of you why, one of the reasons that I may probably hear is that "Our math teacher told us!"  - which should not be the case..

Maybe you are wondering why or how can 1 be equal to 2. Let us look at the following proof: First, let us have two real numbers a and b where Using the addition property of equality, let us add b on both sides. If we simplify both sides.