How many Sides does a polygon have with 140 degree angles?

Answer 1

The sum of the angles : (n - 2)180°

The measure of one angle: [(n - 2)180°]/n

Then we have:

[(n - 2)180°]/n = 140° multiply by n to both sides;

[(n - 2)180°] = 140°n

180°n - 360° = 140°n divide by 20 to both sides;

9°n - 18° = 7°n subtract 7°n and add 18° to both sides;

2°n = 18° divide by 2° to both sides;

n = 9

Thus, the regular polygon has 9 sides.