Polygons & Angles

A polygon is a closed figure formed by a finite number of straight line segments connected end to end.

Interior angles are the angles formed inside a polygon, while exterior angles are formed outside the polygon when a side is extended.

The sum of the interior angles of a polygon can be calculated using the formula: (n-2) × 180°, where n is the number of sides.

The formula for finding one exterior angle of a regular polygon is 360°/n, where n is the number of sides.

The sum of the exterior angles of any polygon is always 360°.

An octagon is a polygon with eight sides and eight angles.

A regular 18-gon has 18 sides.

The measure of one interior angle of a regular octagon is 135°.

The sum of the interior angles of a decagon (10-sided polygon) is 1440°.

As the number of sides increases, the sum of the interior angles increases according to the formula (n-2) × 180°.