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Find the measure of the central angle.

the circle has a circumference of 9 and the arc length is 1. Use 3.14 for pie.

User TBD
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1 Answer

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To start with we have to write down what we know. pi=3.14, r=9, arc length is 1. x is the angle we are trying to find. Saying that the radius is 9

There is an equation that states that the arc length is equal to x/360 (the fraction of the circle) multiplied by the circumference or 2 times pi times the radius.

L= (x)/(360) * 2 \pi r
where * means multiply.

1= (x)/(360) * 3.14 * 9
Simplify

1= (x)/(360) *28.26
Take the 28.26 over to the other side of the equation, where it then it divides the 1.

(1)/(28.26) = (x)/(360)
This becomes:
0.035= (x)/(360)
Then the 360 is brought over to the other side and multiplies the 0.035:

360*0.035=x
And finally simplify the whole equation and we get our answer.

x=12.739 degrees x=12.7 degrees
User Sannu
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