"A circle is modified so that it will measure a total of 30m around the major arc AB and the chord AB"

Find the radius

http://209.85.48.8/9963/162/upload/p2209738.gif

I don't know where to start.

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- Jul 26th 2010, 03:08 AMCthul[Arcs, sectors and segments] Finding the arc
"A circle is modified so that it will measure a total of 30m around the major arc AB and the chord AB"

Find the radius

http://209.85.48.8/9963/162/upload/p2209738.gif

I don't know where to start. - Jul 26th 2010, 05:34 AMSoroban
Hello, Cthul

Quote:

The perimeter of the shape formed by major arc and chord is 30 m.

Find the radius

Code:`* * *`

* *

* *

* *

* O *

* ♥ *

* r *120* r *

* *

* * * *

A ♥ - - - - - - - ♥ B

* *

* * *

The circumference of the circle is:

The major arc has length:

Using the Law of Cosines on

. .

Hence: .

The perimeter is: .

. . . . . . . . . . . .

Therefore: .

- Jul 26th 2010, 05:49 AMArchie Meade
- Jul 27th 2010, 03:34 AMCthul
Thanks to both, very helpful steps.