<Qua-2024-742> hint
AD//BC ---><DAC=<BCA=p=<ACD (AC is angle bisector of BCD)
--->AD=DC=AO. Let <ADO=q, <ADO=<AOD=<COB=<CBO=q
Hence q=2p In triangle AOD 2q+p=180, p=36, q=72
Since DB=DC=DA, Let <OAB=s, then 2(p+s)+q---> s=18
Hence <ABC=s+p+q=18+36+72=126.
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