SOLUTION: Calculate the radius of a circle whose area is equal to the sum of the areas of three? circles of radii 2 cm, 3 cm and 4 cm.

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Question 630246: Calculate the radius of a circle whose area is equal to the sum of the areas of three?
circles of radii 2 cm, 3 cm and 4 cm.
Answer by rapaljer(4671) About Me  (Show Source):
You can put this solution on YOUR website!
A=pi%2Ar%5E2

Area of three circles = pi%2A2%5E2+%2B+pi%2A3%5E2+%2B+pi%2A4%5E2
A=pi%2A4+%2B+pi%2A9+%2B+pi%2A16
A=pi%2A29

Area of unknown circle = pi%2Ar%5E2=pi%2A29

Divide both sides by pi:

r%5E2=29

r=sqrt%2829%29+

For additional help with this topic and other algebra topics, please see my own FREE website at www.mathinlivingcolor.com.

Dr. Robert J. Rapalje, Retired
Seminole State College of Florida