We have BAD^=180∘−(29∘+41∘)=110∘, BCD^=82∘+58∘=140∘. Consider the circumcircle γ of △BCD. Since BAD^+BCD^>180∘, point A is interior to γ.
Extend CA beyond A to meet γ at E. By inscribed angles EBD^=ECD^=ACD^=58∘, EDB^=ECB^=ACB^=82∘.
Given that ABD^=29∘, ADB^=41∘ we obtain that BA and DA are bisectors of EBD^ and EDB^ respectively.
Hence A is the incenter of triangle BDE, implying that EA is the bisector of BED^.
From the cyclic quadrilateral BCDE we have
BED^=180∘−BCD^=BEC^=21BED^=20∘ and analogously
DBC^=20∘. In conclusion, ABC^=29∘+20∘=49∘,ADC^=41∘+20∘=61∘.