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so solve
180(n-2)/n = 120
you should have stated that it must be a "regular" hexagon.
(number of sides - 2) × 180° = sum of interior angles
Let's put this formula into action to find the answer to your question:
1. Rearrange the formula to solve for the number of sides:
(number of sides - 2) × 180° = sum of interior angles
number of sides - 2 = sum of interior angles / 180°
number of sides = (sum of interior angles / 180°) + 2
2. Plug in the given interior angle of 120° into the formula:
number of sides = (120° / 180°) + 2
number of sides = 0.6667 + 2
number of sides ≈ 2.6667
Since a polygon cannot have a non-integer number of sides, we need to round the answer to the nearest whole number. Therefore, a polygon with an interior angle measuring 120 degrees has 3 sides.