Answer:
[tex]160[/tex] °
Step-by-step explanation:
An alternative method is to use the exterior angle.
the sum of the exterior angles is ALWAYS 360 °
So you can find the size of the exterior angles of a regular polygon quite easily:
If there are 18 sides ( n = 18 ) , then each exterior angle is:
[tex]\frac{360}{n} =\frac{360}{18} = 20[/tex]°
The sum of the exterior and interior angles is 180° because they are adjacent angles on a straight line.
∴ each interior angle is 180° - 20° = 160°
