A circle and a square have the same area. find the length of the diagonal of the square divided by the radius of the circle.

Let us say that the square have edge = sqrt (pi), then its area is pi since A = edge^2, and therefore the diagonal is pi*sqrt (2).

Meanwhile the circle of radius 1 has area pi since area of circle is A = pi * radius^2.

Therefore we get that the diagonal of the square divided by the radius is:

diagonal / radius = pi*sqrt (2) / 1 = pi*sqrt (2)