How would I prove the congruency of these triangles?

Step-by-step explanation:
the radius cuts the segment into two equal parts because it is perpendicular to the chord
Answer:
Step-by-step explanation:
As O is the mid point of the circle
Similarly, B also becomes the mid point of the line AC.
So, line OB divides AB and BC equally.
Hence, lines AB = AC, but they are asking to prove congruency of triangles.
So, u have to join OA and OC.
Same way, line OB divides ∠OBA and ∠OBC.
So it is proved that AB = AC