The figure shows a hexagon ABCDEF. Angle a = angle d = 100°, The other angles are of same size. Find the value of angle abc.

Question



Answer 1

(n-2)180 = the sum of the interior angles of a polygon with n sides

for a hexagon, n=6

(6-2)180 = 4(180) = 720 degrees total

each angle of a regular hexagon = 720/6 = 120 degrees

for an irregular hexagon with 2 angles = 100 and the other 4 angles of equal size, 720-200 = 520. 520/4 = 130 degrees for each of the other 4 angles