Question:
For a regular 12-sided polygon, find each of the following:
a) the measure of an exterior angle _____?
b) the measure of an interior angle _____?
Solution:
Note that, for any point in a polygon, the interior angle and exterior angle are on a straight line and therefore add up to 180°. This means that we can work out the interior angle from the exterior angle and vice versa:
a) the measure of an exterior angle is given by the following formula:

b) the measure of an interior angle is given by the following formula:
