area of shaded part = area of circle - area of the square
= pi (6)^2 - area of the square.
Area of square = (m of one side) ^2
measure of of side is found as follows:-
6^2 = 2s^2 where m of the side = 2s
s = sqrt 18 so side of square = 2 sqrt18
area of square = (2 sqrt18)^2 = 4*18 = 72
area of shaded region = 36pi - 72 = 41.1 sq units to neraest tenth