document.write( "Question 627564: how do i find the exterior angle of a convex polygon? \n" ); document.write( "
Algebra.Com's Answer #394979 by MathLover1(20850)\"\" \"About 
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There are two theorems that you can use to find the measure of interior angles of a convex polygon. One theorem works only for triangles. The other theorem works for all convex polygons, including triangles. \r
\n" ); document.write( "\n" ); document.write( "Let's take a look at the theorem for triangles first.\r
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\n" ); document.write( "\n" ); document.write( "1. The sum of the interior angles of a triangle is always \"180\"°\r
\n" ); document.write( "\n" ); document.write( "Since the polygons can be divided into triangles, and since each triangle has 180°, you just multiply the number of triangles by \"180\"° to get the sum of the \"interior+\"angles.\r
\n" ); document.write( "\n" ); document.write( "\"s=180%28n-2%29\"\r
\n" ); document.write( "\n" ); document.write( "then divide it by \"n\" (number of the sides of a polygon) in order to calculate the measure of the \"interior+\" angle\r
\n" ); document.write( "\n" ); document.write( "\"s=180%28n-2%29%2Fn\"\r
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\n" ); document.write( "\n" ); document.write( "Use this theorem to find the measure of exterior angles of a convex polygon.\r
\n" ); document.write( "\n" ); document.write( "2. The sum of the exterior angles of a convex polygon is \"+always\"\"360\"°\r
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\n" ); document.write( "\n" ); document.write( "Remember that a straight angle is \"180\"°\r
\n" ); document.write( "\n" ); document.write( "The interior angle is always supplementary to an exterior angle at that vertex. They always add to \"180\"°, even for a concave polygon. \r
\n" ); document.write( "\n" ); document.write( "Convex case:\r
\n" ); document.write( "\n" ); document.write( "In the case of convex polygons, where all the vertices point \"outwards\" away form the interior, the \"exterior+\"angles are \"always\" on the \"outside\" of the polygon. \r
\n" ); document.write( "\n" ); document.write( "Although there are \"two\"\"+possible\"\"+exterior+\"angles at each vertex , but we usually only consider one per vertex, selecting the ones that all go around in the same direction, clockwise in the figure.\r
\n" ); document.write( "\n" ); document.write( "Taken one per vertex in this manner, the exterior angles\"+always\" add to \"360\"°
\n" ); document.write( "This is true no matter how many sides the polygon has, and regardless of whether it is regular or irregular, convex or concave.
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