Answer:
x = 60
Step-by-step explanation:
This question is kind of sneaky. You have to watch what is going on. The angle <BXO is a right angle. That's because a line that is bisected joined from the bisection point connect to the center forms a right angle with the chord. Put in much simpler terms, OX is perpendicular to BA and the same thing can be said about YO and AC.
That means you have 3 of the 4 angles known. 120 + 90 + 90 = 300
360 - 300 = 60
x = 60