角MPE=角D+角DMP(1式)角MQF=角A+角AMQ(2式)六边形PEGFQM内角和=角MPE+角E+角G+角F+角MQF+角PMQ=(6-2)*180=720三角形CMB内角和=角B+角C+角PMQ=180故六边形PEGFQM内角和+三角形CMB内角和=角MPE+角E+角G+角F+角MQF+角PMQ+角B+角C+角PMQ=900(3式)将(1式)和(2式)代入(3式)得角A+角B+角C+角D+角E+角F+角G+(角DMP+角AMQ+角PMQ+角PMQ)=900又因为角PMQ=角AMD所以角DMP+角AMQ+角PMQ+角PMQ=角DMP+角AMQ+角PMQ+角AMD=360(周角)角A+角B+角C+角D+角E+角F+角G=900-360=540