This comprehensive guide explores polygons and circles, covering their definitions, properties, and formulas. It provides detailed explanations and examples to help students understand these geometric concepts.

**Overall Summary:**

This unit covers polygons and circles, two fundamental geometric shapes:

- Polygons are classified by their number of sides, from triangles to decagons.
- The sum of interior angles of a polygon can be calculated using the formula (n-2) × 180°.
- Circles are defined by their center and radius, with formulas for circumference and area.
- Key circle concepts include chords, sectors, and related calculations.
- The guide includes examples and definitions of important geometric terms.