document.write( "Question 1183295: A polygon has two interior angles of 120 degrees each and the others are 150 degrees.Calculate a. The number of sides of the polygon b. The sum of interior angles \n" ); document.write( "
Algebra.Com's Answer #813531 by ikleyn(52839)![]() ![]() You can put this solution on YOUR website! . \n" ); document.write( " \r\n" ); document.write( "Let \"n\" be the number of sides of the polygon (the same as the number of vertices).\r\n" ); document.write( "\r\n" ); document.write( "\r\n" ); document.write( "Two interior angles are 120 degrees each, and the other (the rest) (n-2) interior angles are 150 degrees each.\r\n" ); document.write( "\r\n" ); document.write( "\r\n" ); document.write( "Write equation for the sum of all interior angles\r\n" ); document.write( "\r\n" ); document.write( "\r\n" ); document.write( " 120 + 120 + (n-2)*150 = (n-2)*180.\r\n" ); document.write( "\r\n" ); document.write( "\r\n" ); document.write( "Simplify and find \"n\"\r\n" ); document.write( "\r\n" ); document.write( "\r\n" ); document.write( " 240 + 150n - 300 = 180n - 360\r\n" ); document.write( "\r\n" ); document.write( " 240 + 360 - 300 = 180n - 150n\r\n" ); document.write( "\r\n" ); document.write( " 300 = 30n\r\n" ); document.write( "\r\n" ); document.write( " n = 300/30 = 10.\r\n" ); document.write( "\r\n" ); document.write( "\r\n" ); document.write( "Thus the polygon has 10 sides and 10 vertices.\r\n" ); document.write( "\r\n" ); document.write( "\r\n" ); document.write( "The sum of the interior angles is (10-2)*180 = 8*180 = 1440 degrees. ANSWER\r\n" ); document.write( "\r \n" ); document.write( "\n" ); document.write( "Solved.\r \n" ); document.write( " \n" ); document.write( " \n" ); document.write( "\n" ); document.write( " \n" ); document.write( " |