Regular Polygon Inscribed in a Circle

• With centre O , draw the given circle.
• Draw a diameter AB and divide it into five equal parts (same number of parts as the number of sides) and number them as shown.
• With centres A and B and radius AB , draw arcs intersecting each other at M.
• Draw a line joining points M and A_2 intersecting the circle at I. Then AI is the length of the side of the pentagon.
• Starting from I , step – off on the circle, divisions IJ , JK , KL equal to AI.
• Draw segments AI , IJ , JK ,KL and LI thus completing the pentagon.

Area of Circle - I

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