How to Find the Exterior Angle of a Regular Polygon

Finding the Exterior Angle of a Regular Polygon

Each exterior angle of a regular polygon is given by the formula:

In this formula, n is the number of sides of the regular polygon.

How to Find the Exterior Angle of a Regular Polygon

Finding the exterior angle of a regular polygon is easy.

Question

What is the exterior angle of a regular octagon?

Step-by-Step:

1

Start with the formula:

Exterior angle = 360° ⁄ n

Don't forget: / means ÷.

2

Substitute the number of sides into the formula.

An octagon has 8 sides. In our example, n = 8.

Exterior angle = 360° ÷ 8

Exterior angle = 45°

Answer:

The exterior angle of a regular octagon is 45°.

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See Also

What is an angle?