the area of a rectangle is well, just length * width, so 2x1, or just 2 then
now, what's the radius of a circle with an area of 2?
[tex]\bf \textit{area of a circle}\\\\
A=\pi r^2\qquad
\begin{cases}
r=radius\\
------\\
A=2
\end{cases}\implies 2=\pi r^2\implies \cfrac{2}{\pi }=r^2
\\\\\\
\boxed{\sqrt{\cfrac{2}{\pi }}=r}[/tex]
