What is the radius of a circle with a circumference of 28 pi?

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Answer 1 · 2018-05-09T17:21:22

The radius is #14# units.

Start by finding the diameter; the formula for circumference is #pid#, so set up an equality:

#28pi#=#c#
#28pi#=#pid#

Divide both sides by #pi#:

#(28pi)/(pi)=(pid)/(pi)#

#(28color(red)(cancel(pi)))/(color(red)(cancel(pi)))#=#(color(red)(cancel(pi))d)/(color(red)(cancel(pi)))#

#28=d#

Diameter is twice as large as radius, so divide your diameter by 2 to get radius.

#d/2=r=28/2=color(red)(14)#

Therefore, your radius is #14# units.