Polygon Interior and Exterior Angle Sums

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Polygon Interior and Exterior Angle Sums

Polygon Interior and Exterior Angle Sums
\[\begin{aligned} S_i &= (n-2)180^\circ \\ S_e &= 360^\circ \end{aligned}\]

Variables

Si = sum of interior angles (deg)
Se = sum of exterior angles (deg)
n = number of sides

Description

What is this formula?

This set of formulas calculates the sum of the interior and exterior angles of a polygon using the number of sides.


When to use it

Use these formulas in geometry, mathematics education, engineering, and drafting when analyzing polygonal shapes.


Example

For a polygon with 8 sides:


Interior angle sum:

Si = (8-2)*180 = 1080°


Exterior angle sum:

Se = 360°


Applications

- Polygon analysis

- Geometric construction

- CAD and technical drawing

- Educational mathematics

- Architectural design


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