A regular polygon is such that its interior angle exceeds three times the exterior angle by 20^o. Find

A regular polygon is such that its interior angle exceeds three times the exterior angle by 20^o. Find the number of sides the polygon has.

Answers

Let interior angle be x.

exterior angle is (180 - x)^o

x = 3(180 - x) + 20

x = 540 + 20

4x = 540 + 20

4x = 560; x = 140

exterior angle

= (180^o - 140^o) = 40^o

the number of sides is

$\frac{360}{40}$ = 90 sides

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johnmulu answered the question on June 12, 2017 at 06:40

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