SAT Math : How to find an angle in a polygon
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Example Question #11 : How To Find An Angle In A Polygon
To the nearest whole degree, give the measure of each interior angle of a regular polygon with 17 sides.
The measure of each interior angle of an 
Setting 
The correct choice is therefore 
Example Question #12 : Other Polygons
Each interior angle of a regular polygon has measure 
The easiest way to work this is arguably to examine the exterior angles, each of which forms a linear pair with an interior angle. If an interior angle measures 
The measures of the exterior angles of a polygon, one per vertex, total 
Multiply both sides by 
The polygon has 72 vertices and, thus, 72 sides.
Example Question #381 : Plane Geometry
A regular polygon has a measure of 
To determine the measure of the angles of a regular polygon use:
Angle = (n – 2) x 180° / n
Thus, (n – 2) x 180° / n = 140°
180° n - 360° = 140° n
40° n = 360°
n = 360° / 40° = 9
Example Question #93 : Plane Geometry
A regular seven sided polygon has a side length of 14”. What is the measurement of one of the interior angles of the polygon?
154.28 degrees
180 degrees
252 degrees
257.14 degrees
128.57 degrees
128.57 degrees
The formula for of interior angles based on a polygon with a number of side n is:
Each Interior Angle = (n-2)*180/n
= (7-2)*180/7 = 128.57 degrees
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