Points A, B, C, D, E are on the circumference of a circle with center O. BD = BE, CAD = 18^, BEC = 51^. Find ADC.

Here's how to solve the problem step-by-step:

Given information:

• Points A, B, C, D, E are on the circumference of a circle with center O.
• $BD = BE$ (This means $\triangle BDE$ is an isosceles triangle).
• $\angle CAD = 18^\circ$.
• $\angle BEC = 51^\circ$.

Key Circle Theorems:

1. Angles subtended by the same arc at the circumference are equal.
2. In an isosceles triangle, the angles opposite the equal sides are equal.
3. The sum of angles in a triangle is $180^\circ$.

a) Find $\angle ADC$.

Step 1