Polygon Interior and Exterior Angles

Concave Polygon

"caves in" ... at least one diagonal can be drawn on the exterior of the polygon

What is the measure of each interior angle of a regular Pentagon?

108

What is the measure of each exterior angle of a regular triangle?

120

What is the sum of the interior angles of a regular nonagon?

1260

What is the measure of an interior angle of a regular octagon?

135

What is the sum of the interior angles of a decagon?

1440

What is the measure of each interior angle of a regular dodecagon?

150

What is the measure of each exterior angle of a regular decagon?

36

What is the sum of the exterior angles of an octagon?

360

What is the sum of the interior angles of a pentagon?

540

What is the measure of each interior angle of a regular triangle?

60

What is the measure of an exterior angle of a regular pentagon?

72

What is the sum of the interior angles of a hexagon?

720

What is the measure of an exterior angle of a regular quadrilateral?

90

Convex polygon

all diagonals are located on the inside of the polygon

Regular polygon

equilateral and equiangular