Since the hexagon is equiangular, all its exterior angles have the same measure, and since there are six of them, that is
360/6 = 60 degrees.
There's a second way to solve this. [ You could use the fact that the measures of an interior angle and the corresponding exterior angle add up to 180 degrees. Again, because the hexagon is equiangular, all its angles measure 120 degrees, so the external angles measure
180 - 120 = 60 ... (More)