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Finding the Area of a Circle with Inscribed Squares

Jul 4, 2024

Finding the Area of a Circle with Inscribed Squares

Key Concepts

  • Area of Squares and Circle: Understanding the relationship between squares inscribed in a circle.
  • Equations of a Circle: Utilizing standard circle equations to solve for unknowns.
  • Coordinate System: Applying a rectangular coordinate system to identify points on a circle.

Circle and Squares Overview

  1. Identify Square Properties:

    • Each square's area = 16.
    • Side length of each square = 4.
  2. Circle Equations:

    • Area of a circle: A = Ï€r²
    • Equation of a circle: (x - h)² + (y - k)² = r²
      • where (h, k) is the center and r is the radius.

Steps to Determine the Circle's Area

  1. Identify Key Points on Circle: Four Inscribed Squares Touching Points

    • Coordinate system used to identify points.
    • Points identified: (0, 0), (0, 4), (-16, -4)
  2. Solve for Variables in Circle Equation:

    • Equations derived from points:
      1. (0 - h)² + (0 - k)² = r²
      2. (0 - h)² + (4 - k)² = r²
      3. (-16 - h)² + (-4 - k)² = r²
    • Simplify and solve for h, k, and r systematically.
  3. Elimination and Simplification: Solving for k

    • Starting with two top equations:
      • h² + k² = h² + (4 - k)²
      • Simplify: k² = 16 - 8k + k²
      • Result: k = 2.
  4. Solve for Remaining Variables: Solving for h

    • Substitute k = 2 back into equations.
      • (4 - k)² simplifies to 2² = 4
      • -4 - k simplifies to -6² = 36
    • Solve the simplified equations:
      • -16 - h simplifies to (-16 + 9)² = 81
      • Result: h = -9.

Final Calculation of Radius and Area

  1. Substitute h and k into Equations

    • Validate by confirming consistency in equations.
    • Resultant r² = 85
  2. Calculate Circle's Area:

    • A = Ï€ × 85
      • Result: Circle's area is 85Ï€ square units.

Conclusion

  • The area of the circle with inscribed squares is 85Ï€ square units.