A square with sides of 12 units is inscribed in a circle. What is the value of $K$ if the area of the circle is $K\pi$ square units?
the diameter of the circle will be the diagonal of the square, which is 12$\sqrt2$, and the area of the circle is $\pi$(d/2)$^2$=$K\pi$=72$\pi$, so therefore, the value of $K=\boxed{72}$