If the length of AB is 20cm.

What is the area between the two circles?

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- May 8th 2006, 02:13 PMNatasha1What is the area between the two circles?
If the length of AB is 20cm.

What is the area between the two circles? - May 8th 2006, 08:01 PMCaptainBlackQuote:

Originally Posted by**Natasha1**

the radius of the smaller circle and the radius of the outer circle .

Then triangle is a right triangle with hypotenuse

and the other sides , and . Therefore by Pythagoras:

,

or:

The area of the annulus is:

RonL