math

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the radius of a circle when the numeric values of the circumference and area are equal.


circumference = 2*pi*r
area = pi*r^2
Set them equal and solve for r.


thanks! i understand it now!


2*3.14*r=3.14*r^2
6.28*r=3.14*r^2
r=3.14
Is that right? It doesn't seem to be.


2*3.14*r=3.14*r^2
6.28*r=3.14*r^2 You are ok to here.
r=3.14
Is that right? It doesn't seem to be.
Then divide both sides by 3.14
(6.28/3.14)*r=(3.14/3.14)r^2
2*r=1*r^2
Now divide both sides by r
2*(r/r)=(r^2/r)
2*1=r
2=r

But there is an easier way to have done it. Start at the beginning and we have
2*pi*r=pi*r^2
The pi cancels since it is on both sides.
Divide both sides by r to obtain
2=r

I hope this helps.

thanks, it did help!!

the diameter of a bicycle wheel is 26 in. How far will you travel after one complete turn of the wheel?

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