What are supplementary angles? They are two angles that when added together make 180 degrees on a straight angle line. Hard to picture that? Then watch this video and see how the instructor illustrates this on a diagram.

How can a straight line be called a straight angle? Can angles be combined to form a straight angle? Yes, supplementary angles can be combined to make a straight angle and that is how one can find the value of a missing angle. Take a...

If you add the value of the three interior angles in a triangle will it equal 180 degrees? Yes it will. The instructor illustrates and proves the Triangle Sum Theorem. Follow closely as she explains her proof.