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Video Seven: Area of Circles

Video Seven: Area of Circles

Author: Shelly Hicks
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Tutorial

Calculating the Area of a Circle

Area of a Circle

Key Ideas:

Formula for area of a circle = pi X radius X radius or

 Area space equals space straight pi space straight X space straight r space straight x space straight r space space left parenthesis o r space i t space c a n space b e space w r i t t e n space a s space space A space equals space πr squared right parenthesis

  • Remember pi is a Greek letter, straight pi
  • To estimate the area of a circle, we use a value of 3 for straight pi
  • To find a more exact value for the area of a circle, we use a value of 3.14 for straight pi