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the sum of the interior angles of a polygon is three times the sum of its exterior angles . Determine the number of sides of the polygon
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(n-2)*180 = 3*360 ---> (Everybody knows about the left side. It is the sum of internal angles of any n-sided polygon.
Many know about the number 360 in the right side. 360° is the sum of the external angles of any n-sided polygon.)
n- 2 = = 3*2 = 6 --->
n = 6 + 2 = 8.
Check. (8-2)*180 = 6*180. 6*180 in the left = 3*360 in the right. Yes!!!
Answer. n = 8. ( Octagon ! )