The exterior angles of a regular polygon are all equal and their sum is 360º. This is so for any regular polygon.
So to calculate the measure of one exterior angle of a regular polygon you have to divide 360º by the number of sides of the polygon.
[tex]\frac{360º}{n}[/tex]
Where "n" is the number of sides.
1) The first polygon is a pentagon, with n=5 sides
The measure of one of its external angles is:
[tex]\frac{360}{5}=72º[/tex]
2) The second polygon is a square, with n=4 sides.
The measure of one of its external angles can be calculated as:
[tex]\frac{360}{4}=90º[/tex]
3) The third polygon is an octagon, with n=8 sides.
The measure of one of its external angles can be calculated as:
[tex]\frac{360}{8}=45º[/tex]
4) The fourth polygon is a hexagon, with n=6 sides.
The measure of one of its external angles can be calculated as:
[tex]\frac{360}{6}=60º[/tex]
