SOLUTION: The interior angle of a regular polygon is thrice the exterior angle .how many sides has the polygon

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Question 976667: The interior angle of a regular polygon is thrice the exterior angle .how many sides has the polygon
Answer by htmentor(1343) About Me  (Show Source):
You can put this solution on YOUR website!
The sum of the interior and exterior angles must be 180 deg.
Let x = the measure of the exterior angle
Then x + 3x = 180 -> 4x = 180 -> x = 45
The exterior angles of a regular polygon add up to 360, which means each exterior angle is 360/n [n=number of sides]
So we have 360/n = 45 -> n = 360/45 = 8
So the polygon is an octagon (8 sides)