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Area of a Sector
Geometry · 9th Grade · Circles · Quarter 4

Area of a Sector

Derive the formula for the area of a sector, which represents a 'slice' of a circle. You will apply this formula to solve real-world problems involving circular regions.

Common Core State StandardsCommon Core State Standards: Geometry - Circles - Find arc lengths and areas of sectors of circlesCommon Core State Standards: Geometry - Circles - Derive the formula for the area of a sector

About This Topic

Derive the formula for the area of a sector, which represents a 'slice' of a circle. You will apply this formula to solve real-world problems involving circular regions.

Key Questions

  1. Explain how the formula for the area of a sector is derived from the formula for the area of a circle.
  2. Analyze problems that require finding the area of a sector or a segment of a circle.
  3. Compare the formulas for sector area when the central angle is given in degrees versus radians.

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Edited by Adriana Perusin, Editor-in-Chief, Flip Education