In Fig. 16.195, ABCD is a cyclic quadrilateral in which ∠BAD=75°, ∠ABD=58° and ∠ADC=77°, AC and BD intersect at P. Then, find ∠DPC.
∠DBA = ∠DCA = 58° (Angles on the same segment)
In triangle DCA
∠DCA + ∠CDA + ∠DAC = 180°
58° + 77° + ∠DAC = 180°
∠DAC = 45°
∠DPC = 180° - 58° - 30°
= 92°