document.write( "Question 247321: what is the number of sides a polygon has if the sum of the degree measures of the interior angle is 180°? \n" ); document.write( "
Algebra.Com's Answer #180438 by Edwin McCravy(20060)\"\" \"About 
You can put this solution on YOUR website!
what is the number of sides a polygon has if the sum of the degree measures of the interior angle is 180°?
\n" ); document.write( "
\r\n" );
document.write( "The formula for the \"S\", the sum of the degree measures of the interior\r\n" );
document.write( "angles of a polygon with \"n\" sides is \r\n" );
document.write( "\r\n" );
document.write( "\"S=%28n-2%29%2A%22180%B0%22\"\r\n" );
document.write( "\r\n" );
document.write( "So we substitute \"%22180%B0%22\" for \"S\"\r\n" );
document.write( "\r\n" );
document.write( "\"%22180%B0%22=%28n-2%29%2A%22180%B0%22\" \r\n" );
document.write( "\r\n" );
document.write( "Divide both sides by \"180%B0\"\r\n" );
document.write( "\r\n" );
document.write( "\"%22180%B0%22%2F%22180%B0%22=%28n-2%29%2A%22180%B0%22%2F%22180%B0%22\"\r\n" );
document.write( "\r\n" );
document.write( "\"1=n-2\"\r\n" );
document.write( "\r\n" );
document.write( "\"3=n\"\r\n" );
document.write( "\r\n" );
document.write( "So the answer is:  It has 3 sides.\r\n" );
document.write( "\r\n" );
document.write( "That means the polygon is a triangle.  \r\n" );
document.write( "\r\n" );
document.write( "I'll bet you've known all along that the \r\n" );
document.write( "\r\n" );
document.write( "measures of the interior angles of a triangle\r\n" );
document.write( "\r\n" );
document.write( "is 180°, now haven't you?  Maybe you didn't\r\n" );
document.write( "\r\n" );
document.write( "know that a triangle was a polygon, but it is!\r\n" );
document.write( "\r\n" );
document.write( "It's a polygon with three sides!\r\n" );
document.write( "\r\n" );
document.write( "Edwin
\n" ); document.write( "
\n" );