Topics › Geometry › Interior Angle Sum of a Polygon
Geometry · G-CO

Interior Angle Sum of a Polygon

The interior angle sum of an n-gon is (n−2)×180°. Each interior angle of a regular n-gon is (n−2)×180°/n.

GeometryCommon Core HSG-CO.A.1G-COVerified correct ✓

Worked examples

What is the sum of the interior angles of a triangle?
Answer: 180
A hexagon has interior angles measuring 120, 120, 120, 120, 120, and one unknown angle. Find the unknown angle.
Answer: 120

Every problem on Pounce is generated and checked by code — never a wrong answer key.

Master Interior Angle Sum of a Polygon

Code-verified problems at exactly the right level, explained the way your kid learns.

Start your free trial 🐾

Build up to this

Angle Pairs — Supplementary, Complementary, Vertical

More Geometry topics

Angle Pairs — Supplementary, Complementary, VerticalCoordinate Rules for TransformationsSide Ratios in Similar FiguresPythagorean Theorem — Find Missing SidesSpecial Right Triangles — 30-60-90 and 45-45-90Trigonometric Ratios — sin, cos, tanSolve Right Triangles Using TrigCircle — Circumference and Area