SSC CHSL Model Paper 7

∠ABC + ∠ADC = 180° (sum of opposites angles of cyclic quadrilateral is 180°) ⇒ ∠ZABC +110° = 180° ( ABCD is a cyclic quadrilateral)
⇒ ∠ABC = 180 -110
⇒ ∠ABC = 70° (∵ AD ∥ BC)
∴ ∠ABC + ∠BAD = 180° (Sum of the interior angles on the same side of transversal is 180°)
70° + ∠BAD = 180°
⇒ ∠BAD= 180°- 70°= 110°
⇒ ∠BAC+∠DAC =110°
⇒ 50° + ∠DAC =110°
⇒ ∠DAC =110°-50° = 60°