SOLUTION: AB and BC are adjacent sides of a regular polygon. Angle ABC=140 degrees. Calculate the number of sides of the polygon.
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Question 767368: AB and BC are adjacent sides of a regular polygon. Angle ABC=140 degrees. Calculate the number of sides of the polygon. Answer by ramkikk66(644) (Show Source):
You can put this solution on YOUR website! Let the polygon be of n sides.
Total sum of angles of a polygon of n sides = (n - 2)*180 degrees.
In a regular polygon, all internal angles are equal.
In this case, each internal angle = 140.
Number of internal angles = number of sides of the polygon = n.
So, 140*n = (n-2)*180 = 180*n - 360
40*n = 360
n = 9
The polygon has 9 sides.
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