Polygon Interior Angle Sum Theorem

The sum of the interior angles of a polygon is __________________ where n is the number of sides.

• (n - 2)180

• (n - 1)180

• 360

• (n - 3)(180)

Solve for x. 

• 100

• 120

• 125

• 130

Find the measure of ONE interior angle of a regular dodecagon.

• 150

• 120

• 1800

• 20

Find the sum of the interior angles of a nonagon.

• 1260

• 900

• 1620

• 180

• 1720

• 1440

• 2340

• 4500

Find the measure of one interior angle in regular 25-gon. Round your answer to the nearest tenth if necessary.

• 164.3⁰

• 167.1⁰

• 165.6⁰

• 166.7⁰

Find the measure of angle E.

• 9

• 97°

• 48°

• 79°

Find the value of X.

• 60

• 120

• 85

• 55

• The measure of the largest interior angle

• The number of sides of the polygon

• Nothing

• The number of triangles that compose the polygon

Find the value of x.

• 540⁰

• 121⁰

• 134⁰

• 360⁰