Its 11/15. u find the LCM of 3 and 5 which is 15 and to get to 15 from 3 and 5 you need to times 5 by 3 and 3 by 5 then u add the answers but keep the same denominator
Since the diameter of the circle is a perpendicular bisector to the chord, x and 6 must be equal and therefore x=6. It also bisects the arc, meaning that y=75. Hope this helps!
