The exterior angle of a regular polygon is two seventh of the interior angle. Find the number of sides of this polygon.

Answers

Let interior angle be x

exterior =

$\frac{2}{7}$ x

x +

$\frac{2}{7}x$ = 180;

$\frac{9x}{7}$ = 180

$\frac{180 \times 7}{3}$ = x;

x = 140

the number of sides is

$\frac{360}{40}$ = 9

johnmulu answered the question on June 12, 2017 at 06:52

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