The complete circumference is given by the following equation: (4y + 6) + (7y-7) + (20y-11) = 360 Rewriting we have: 31y - 12 = 360 Clearing and we have: 31y = 360 + 12 y = 372/31 y = 12 Then, the measure of the ABC arc is: (4y + 6) + (20y-11) = (4*(12)+6) + (20*(12)-11) = 283 degrees Answer: 283 degrees
