SOLUTION: A circular arc of length 4 feet subtends a central angle of 180o. Find the radius r of the circle. r = Please explain Thank you

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Question 929458: A circular arc of length 4 feet subtends a central angle of 180o. Find the radius r of the circle.
r =
Please explain
Thank you
Found 2 solutions by MathLover1, lwsshak3:
Answer by MathLover1(20850) About Me  (Show Source):
You can put this solution on YOUR website!
A circular arc of length 4 feet subtends a central angle of 180° degrees. Find the radius of the circle in feet.
where,
theta = central angle and r = radius of the circle.

radius+=+%28arc_+length%29%2Ftheta,.... but theta has to be in RADIANS
theta=180° => pi=3.14 radians
r+=+%28arc_+length%29%2Ftheta
r=+4ft%2F3.14
r=+1.27+feet+
or this way:
thus,
4ft+=+2+%2A+3.141+%2A+r+%2A+%28180%2F360%29
=> 4ft+=+cross%282%29+%2A+3.141%281%2Fcross%282%29%29+%2A+r
=> 4ft+=+3.14%2A+r
=> r+=+4ft%2F3.14
=r=+1.27feet+
or this way:
radius+=+Arc_+length+%2F+angle where angle is
(x*pi/180)
Arc+=+4ft+%2F+%28%28cross%28180%29%2Api%29%2Fcross%28180%29%29+
Arc+=+4ft+%2F+pi+
Arc+=+4ft+%2F+%283.14%29+
=+1.27feet+




Answer by lwsshak3(11628) About Me  (Show Source):
You can put this solution on YOUR website!
A circular arc of length 4 feet subtends a central angle of 180o. Find the radius r of the circle.
***
s=r%28theta%29, s=arc, r=radius, theta=central angle(radians)
180˚=π radians
4=rπ
r=4/π ft