In Fig. 16.185, if ABC is an equilateral triangle. Find ∠BDC and ∠BEC
Since, ABC is an equilateral triangle
Then,
∠BAC = 60o
Therefore,
∠BDC = ∠BAC = 60o (Angles in the same segment)
Since, quadrilateral ABEC is a cyclic quadrilateral
Then,
∠BAC + ∠BEC = 180o
60o + ∠BEC= 180o
∠BEC = 180o – 60o
= 120o