In the diagram, AOB is a sector of a circle with angle AOB = 60. OY is drawn perpendicular to AB and intersects AB at X. What is the length of AB?
Using the Law of Cosines on \(\triangle AOB\) gives us \(AB = \sqrt{20^2 + 20^2 - 2\times 20 \times 20 \cos 60} = \color{brown}\boxed{20}\)