Equal parts in a circle

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Dividing a circle in to parts and exploring to divide it into equal parts is show in this activity.

Objectives

To divide a circle into equal parts

Estimated Time

30 minutes

Prerequisites/Instructions, prior preparations, if any

Prior knowledge of point, lines, angles, polygons

Materials/ Resources needed

  • Digital : Computer, geogebra application, projector.
  • Non digital : Worksheet and pencil, compass, strings
  • Geogebra files : Equal parts in a circle .ggb


Download this geogebra file from this link.


Process (How to do the activity)

  • Plot 4points on the circle; join these points to the center of the circle. Are all the parts equal?
  • How many parts is the circumference divided into? Identify the part of the circumference that is the largest?
  • If the segments connecting the points to the center are equal, what is it that makes the part bigger than the others?
  • Establish concept of arc.
  • Which of these parts the largest? How can you say it is largest? Which parameter defines the largeness?
  • What do you notice about the angles made at center by the four parts of the circle. Which part of the circle has the largest angle?
  • What is each part of the circle called? - Establish sector
  • When will all the four parts of the circle be equal?
  • What is the total angle made at the center of the circle?