$$findTHENUMBEROFSIDESOFAPOLYGONIFTHESUMOFITSINTERIORANGLEIS900DEGREE$$
900*dTHENUMBEROFSIDESOFAPOLYGONIFTHESUMOFITSINTERIORANGLEIS*DEGREE*IM*f*n