Question 703883: What is the measure of each exterior angle of an equilateral triangle?
Answer by KMST(5328)   (Show Source):
You can put this solution on YOUR website! For a polygon where all the angles have the same measure
(like an equilateral triangle, a square, a rectangle, a regular hexagon, etc)
the measure of an exterior angle equals
 divided by the number of sides.
So for an equilateral triangle,
each exterior angle measures 
Here's why:
When you are drawing a polygon,
at each vertex, to "turn the corner",
you have to change direction by a certain angle.
That angle if the exterior angle.
For a square, you turn  at each corner,
and if you keep going,
as you are retracing the first side,
you have turned four times,
for a total of  ,
and you are going in the same direction as when you started.
For any regular polygon of  sides,
the exterior angles have the same measure  ,
and  , so 
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