How big is each interior angle in a regular decagon? would this be 4.4 (144/10)?

How big is each exterior angle of a regular decagon?

Is this 36? (360/10)

2 answers

Isnt there a theorem that the sum of the interior angles is
180(n-2), so then each interior angle of a regular n-gon would be\
180(n-2)/n
Each angle measures 144 degrees.

http://www.coolmath.com/reference/polygons.html

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