I absolutely love teaching Geometry! It was my favorite class in high school and in college. I love it because you can “see” the math and you can “see” how it works. So when I got to teach the attributes of triangles, I was super excited!
Types of Angles, Including Complimentary and Supplementary
Interior Angles of a Triangle
They were shocked when the first triangle resulted in 180 degrees or a straight line. Then we predicted on another triangle. Again, most of the students thought it would be bigger than a right angle but not a straight line. They were wrong, it was a straight line! Around the fourth example, everyone knew that every triangle had angles that when added together resulted in 180 degrees or a straight line!