Question

One external angle of a regular polygon is 18 degree. What's is the sum of the external angles

Answer 1

hello..

Its interior angle is 180 deg - 18 deg = 162 deg.
The total measure of its angles is 162*18= 2,916 deg.

Each exterior angle of a regular polygon = 20 deg. So the polygon has 360/20 = 18 sides.

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