SOLUTION: how can you determine the measure of an exterior angle of a regular dodecagon

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Question 290709: how can you determine the measure of an exterior angle of a regular dodecagon
Answer by Earlsdon(6294) About Me  (Show Source):
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To find the measure of an exterior angle of a regular dodecagon, first find the measure of an interior angle then subtract this from 180 degrees.
The measure of an interior angle A%5Bi%5Dof a regular n-sided polygon is given by:
A%5Bi%5D+=+180%28n-2%29%2Fn
A dodecagon has 12 sides so n = 12.
A%5Bi%5D+=+180%2812-2%29%2F12
A%5Bi%5D+=+150degrees
The measure of an exterior angle A%5Be%5D is given by:
A%5Be%5D+=+180-A%5Bi%5D Substitute A%5Bi%5D+=+150
A%5Be%5D+=+180-150
A%5Be%5D+=+30 degrees.