Polygons & Circles

• Circle


  Always 360°
• Diameter


  The longest segment inside the circle, also considered as a chord
• Types of Arc


  • Minor (less than 180°)
  • Major (more than 180°)
  • Semi-Circle (exactly 180°)
• Inscribed angle


  The measure is half the measure of its intercepted arc
• Central angle


  The measure is the same as the measure of its intercepted arc
• Intercepted arc of an inscribed angle

  The measure is twice the measure of the angle
• Parts of a Circle
• Important Formulas Related to Polygon

  • Number of Diagonals (any polygon)
  • Sum of Interior Angles (any convex polygon)
  • Each Interior Angle (any regular convex polygon)
  • Each Exterior Angle (any regular convex polygon)