Question

In the given figure, O is Center of circle. If AC//DB and angle ABC=50 , find angle ACD​

Answer 1

Check the picture below, notice the tickmarks, both sides are equal and they make twin angles on the "base" side of the isosceles triangle.

Answer 2

Explanation:

m∠ACB = m∠CBD = 90° ⇒ m∠CAB = 90° - 50° = 40° = m∠ABD ( Alternate interior angles )

m∠CBD = 90°

m∠CDB = 50 °