ACB+ACD=BCD, 42+38=80. BCD=BAD=80. BCD+BAD+ABC+ADC=360. 80+80+ABC+ADC=360. ABC+ADC=200. ABC=ADC. 2ABC=200, ABC=ADC=100
ACB+ACD=BCD, 42+38=80. BCD=BAD=80. BCD+BAD+ABC+ADC=360. 80+80+ABC+ADC=360. ABC+ADC=200. ABC=ADC. 2ABC=200, ABC=ADC=100