9514 1404 393
Answer:
144°
Step-by-step explanation:
The interior angle of a polygon is the supplement of the exterior angle at that vertex. The sum of exterior angles of a convex polygon is always 360°.
The exterior angle at each vertex of a regular decagon will be 360°/10 = 36°. Then the interior angle is ...
180° -36° = 144° . . . . measure of regular decagon interior angle
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Interior angle A of an n-sided polygon has the measure ...
A = 180° -360°/n = 180°(n -2)/n
