I have tried this problem and don't know where to go:

Show that the area of the Babylonian bullseye is given by A=9/32a^2, where a is the length of the arc (1/3 circumference) also the length of the long transversal of the bull's eye is 7/8a and the the short transversal is 1/2a.

Also known: area of circle = C^2/12, 7/4 = sq root of 3.

Help please!