Question

if the measure of $\angle aob = 155^{\circ}$, what is the measure of $\angle doc$?
enter the answer in the space provided. use numbers instead of words.

Explanation:

Step1: Identify congruent chords

Chord $AB \cong$ Chord $DC$ (marked congruent)

Step2: Relate chords to central angles

In a circle, congruent chords subtend congruent central angles, so $\angle AOB = \angle DOC$.

Step3: Substitute given angle value

$\angle AOB = 155^\circ$, so $\angle DOC = 155^\circ$.

Answer:

155