Arcs of a circle

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  1. Terms related to circles
    • Radius
    • Diameter
    • Circumference
    • Central angle
      • minor arc
      • major arc
    • Inscribed angle
    • Chord
      • perpendicular bisector
    • Tangent
      • point of tangency
  2. How to find the length of an arc?
    • by Central angle
    • by Proportion
    • by Using formula a = Θr

  1. Find the length of the arc in red.

    1. Finding arcs of a circle given radius and angle

    2. Calculate the arc length using the given angle and diameter

    3. Relationship among arcs of a circle, angle, and radius
  2. In the following circle, AD is diameter and BC ⊥ \bot EF, and the radius is 7. Find the measures of:
    Arcs of a circle
    1. arcAB arc AB
    2. arcABE arc ABE
    3. arcAEC arc AEC
    4. ∠BFD \angle BFD
  3. On circle D, arcAB= 105°, arcBC= 140° and arcABC= 245°. Point E is on the circle D too and arcCE= 145°. Explain what E must be on ArcAB.
    Topic Notes