Question

B b) The diagram shows a circle centre O. A, B and Care points on the circumference. DCO is a straight line and DA is a tangent to the circle. Angle ADO = 34° a) Work out the size of angle AOD. (1) 34° Work out the size of angle ABC. Give a reason for your answer. D​

Answer 1

let's recall that the point of tangency for a tangent line to a radius in a circle is alway a right-angle, also let's notice that ∡AOD as well as ∡ABC are both intercepting the same arc.

Check the picture below.