Grade 7Math

Polygon Interior Angle Sum Formula

Grade 7 students in Big Ideas Math Advanced 2 (Chapter 3: Angles and Triangles) learn the Polygon Interior Angle Sum Formula: S = (n - 2) x 180 degrees, where n is the number of sides. This formula works for any polygon by dividing it into (n - 2) triangles from one vertex.

Key Concepts

The sum of interior angles of any polygon with $n$ sides is given by: $$S = (n 2) \times 180°$$.

This formula is derived by dividing any polygon into $(n 2)$ triangles from one vertex.

Common Questions

What is the polygon interior angle sum formula in 7th grade?

The sum of interior angles of a polygon with n sides is S = (n-2) x 180 degrees. For a pentagon (n=5): S = (5-2) x 180 = 540 degrees.

How do you use the polygon angle sum formula to find a missing angle?

Calculate the total angle sum using S = (n-2) x 180. Add all known angles and subtract from S to find the missing angle.

Why does the polygon formula use (n - 2)?

Any polygon can be divided into (n-2) triangles from one vertex. Since each triangle has 180 degrees, total = (n-2) x 180 degrees.

What chapter in Big Ideas Math Advanced 2 covers the polygon interior angle sum?

Chapter 3: Angles and Triangles in Big Ideas Math Advanced 2 (Grade 7) covers the Polygon Interior Angle Sum Formula.

What is the interior angle sum for a hexagon?

A hexagon has 6 sides: S = (6-2) x 180 = 4 x 180 = 720 degrees.