How can you find the radius of a circle from the area?

2 Answers
Mar 27, 2018

Use formula of area of circle

Explanation:

Area of a circle =piR^2
Plug in values and solve for R

R=sqrt("Area"/pi)

Mar 27, 2018

See explanation below

Explanation:

Example:-

Area of a circle=pir^2

If the area=15 cm^2

:.pir^2=15

:.r^2=15/pi

:.sqrt (r^2)=sqrt(15/pi)

:.r=sqrt(15/pi)

:.r=sqrt(4.774648293)

:.r=2.185096861cm or 2.2cm

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check:-

:.pir^2=15

:.pi=15/2.185096861^2

:.pi=15/4.774648292

:.pi=3.141592654