Find the number of sides of a regular polygon whose interior angle is twice the…

Explanation

Let the ext. angle = x
Thus int. angle = 2x
But sum of int + ext = 180 (angle of a straight line).
2x + x = 180
3x = 180
x = 180/3 = 60

Each ext angle = 360/n
=> 60 = 360/n
n = 360/60 = 6

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