Circle O is shown. Line segment J E is a diameter and line segment O B is a radius. A line is drawn from point J to point B to form a chord. Tangents B D and E D intersect at point D outside of the circle. Use the diagram to complete the statements. Can someone explain why the measure of angle EJB is one-half of the measure of the angle BOE? I already know it is one-half but I don't know how to prove it.