As the square has two sides tangent to the circle, the lenght of the side will be de diameter of the circle.
The area of a circle, which is pi*r², in this case is 9a²pi², given that a=6.
So:
[tex]\begin{gathered} \pi r^2=9\cdot a^2\cdot\pi^2\text{ (dividing both sides by pi)} \\ \pi r^2=9\cdot36\cdot3.14^{2} \\ \pi r^{2}=3,194,51 \\ r^{2}=1017,36 \\ r=31,89 \end{gathered}[/tex]
Once r=31.89,, the diameter will be 2*r= 63.78
The area of the square is (63.78)² = 4,067.89u²
