What is the interior and exterior angle of a regular 9 sided polygon?

• The measure of an interior angle in degrees of a regular polygon of n sides is given by the formula: 180 x (n-2) / n

Substituting with n=9, then the answer is that the interior angle = 140

• The measure of an exterior angle in degrees of a regular polygon of n sides is given by the formula: 360/n

Substituting with n= 9, then the answer is that the exterior angle = 40