Construction: Join BD and extend upto E.x = ∠ADC= ∠ADE + ∠CDE= (∠DAB + ∠ABD) + (∠DBC + ∠DCB)| Exterior angle theorem= 35° + (∠ABD + ∠DBC) + 50°= 35° + ∠ABC + 50°= 35° + 45° + 50°= 130°