Figure 5.69 shows two secants AE and AD. Prove that m BAE = (1)/(2) (m arc BD - m arc CE)

The problem refers to Figure 5.69, which shows two secants $AE$ and $AD$ intersecting at an external point $A$.
We are given:

• $m(\angle COE) = a$, which means the measure of arc $CE$ is $a$.
• $m(\angle BOD) = b$, which means the measure of arc $BD$ is $b$.
• $x = m(\angle BAE)$ (or $m(\angle CAE)$ as used in the final line).

Chords $BE$ and $DC$ are drawn.

• The angle $\angle CBE$ is an inscribed angle that subtends arc $CE