Question

Which polygon has an interior angle sum of 1080°?

Answer 1

Octagon

Explanation:

The sum of the interior angles of a polygon is

sum = 180° (n - 2) ← n is the number of sides, so

180° (n - 2) = 1080° ( divide both sides by 180° )

n - 2 = 6 ( add 2 to both sides )

n = 8 ← octagon

Answer 2

Explanation:

• The sum of the interior angles in a regular polygon is given by the formula 180(n – 2), where n is the number of sides in the polygon. An octagon has eight sides, so the sum of the angles of the octagon is 180(8 – 2) = 180(6) = 1080 degrees. Because the octagon is regular, all of its sides and angles are congruent.