First you write down the number of sides that it has.
Let "n" represent the number of sides.
So you have a hexagon which of course is 6 sides.
The next step is to find the SUM of Interior Angles which is (n-2) x 180
So 6 - 2 is 4 and x 180 = 720
The last step is to divide by the original number of sides the polygon has. So since a hexagon has 6 sides, you'd do 720 / 6 =120
Your answer is 120