# How many sides does a regular polygon have if one exterior angle is 72?

Oct 31, 2017

See a solution process below:

#### Explanation:

The Exterior Angles of a Regular Polygon always add up to 360°:

Therefore, we can divide ${360}^{o}$ by ${72}^{o}$ to find the number of sides:

${360}^{o} / {72}^{o} = 5$

The Regular Polygon with Exterior Angles of ${72}^{o}$ is a Pentagon.