Question

How to find number of sides in a regular polygon based on the 900 degree measure of all interior angles?

Answer 1

Sum of Interior Angles = (Number of Sides -2) • 180 degrees
900 = (Number of Sides -2) • 180 degrees
900 / 180 = Number of Sides -2
5 = Number of Sides -2
Number of Sides = 7
Polygon is a heptagon.
http://www.1728.org/polygon.htm