# Sum of interior angles of a Regular Polygon

## Instructions

1. Use the slider to change the number of side.
2. Observe the Sum of interior angles and measure of individual angle below slider.

## Answer the following questions:

What do you mean by Interior angle?

Which formula represents how to find the interior angle sum of any polygon?

What is the SUM of the angle measures in a nonagon (9 sides)?

What is the SUM of the angle measures in a triangle (3 sides)?