SOLUTION: What is the length of the radius of a circle with a central angle measuring 2.5 radians that interceps anark with the length of 15 inches?? Any help please highschool?

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Question 1082990: What is the length of the radius of a circle with a central angle measuring 2.5 radians that interceps anark with the length of 15 inches?? Any help please highschool?
Answer by jim_thompson5910(35256) About Me  (Show Source):
You can put this solution on YOUR website!
The formula we'll use is
s+=+theta%2Ar

where
s = arc length
theta (greek letter theta) = angle in radians ** see note below **
r = radius

We're given
s = 15 inches
theta+=+2.5 radians

and we want to find r

Note: The angle MUST be in radians for this formula to work. If the angle is in degrees, you need to convert to radians first. Or if you want to keep theta in degree mode, you can use the formula s+=+%28theta%2F360%29%2A2%2Api%2Ar which is a bit more complicated.

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Plug the two given items into the formula and solve for r (divide both sides by 2.5)

s+=+theta%2Ar

15+=+2.5%2Ar

15%2F2.5+=+%282.5%2Ar%29%2F2.5

6+=+r

r+=+6

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So the radius is 6 inches