In the diagram below, angle E = 50 degrees, and arc AB, arc BC, and arc CD all have equal length. Find the measure of angle ACD , in degrees.

Arc AB = arc BC = arc CD => x

1/2[x - (360 - 3x)] = 50

x = 115

Arc AD = 15º

If arc AD = 15 then angle ACD = 7.5 degrees