Question 1176902
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*[tex \LARGE \ \ \ \ \ \ \ \ \ \ r\ =\ 2\sqrt{5L}]


*[tex \LARGE \ \ \ \ \ \ \ \ \ \ \frac{r}{2}\ =\ \sqrt{5L}]


*[tex \LARGE \ \ \ \ \ \ \ \ \ \ \(\frac{r}{2}\)^2\ =\ 5L]


*[tex \LARGE \ \ \ \ \ \ \ \ \ \ L\ =\ \frac{r^2}{20}]


Plug in your given values for *[tex \Large r] and do the arithmetic.

																
John
*[tex \LARGE e^{i\pi}\ +\ 1\ =\ 0]
My calculator said it, I believe it, that settles it
*[illustration darwinfish.jpg]

From <https://www.algebra.com/cgi-bin/upload-illustration.mpl> 
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*[tex \LARGE \ \ \ \ \ \ \ \ \ \  
								
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