Q:

# How many vertices does an octagon have?

A:

An octagon has eight vertices. An octagon is a shape with eight sides, which makes eight angles and, therefore, eight vertices.

## Keep Learning

Credit: Gareth Williams CC-BY 2.0

All octagons have eight sides made of straight lines, but only regular octagons have sides that are all equal, like a stop sign. Irregular octagons can even be concave, with some angles pointing inward. However, no side can cross another side in an octagon or in any type of polygon. An octagon is a type of polygon, as a polygon is an enclosed shape with straight lines for sides. Triangles, squares and rectangles are also polygons, as are hexagons. Circles, however, are not polygons.

Sources:

## Related Questions

• A:

To calculate the area of an octagon, substitute the length of one side for s in the formula: area = 2 * s^2 * (1+?2). If the side is measured in centimeters, then the total area is expressed as centimeters squared.

Filed Under:
• A:

In geometry, a shape, or polygon, with eight sides is called an octagon. A common example of an octagon in the real world is the stop sign. The octagon is also used in architecture, and umbrellas often come in an octagonal shape.

Filed Under:
• A:

Some of the most common geometric shapes are the triangle, the square, the pentagon, the octagon and the circle. All of these shapes, except the circle, are polygons, meaning they have a discrete number of sides and angles.