Unfortunately not! You've found the area contained within the square but outside the circle, but that isn't the shaded area.
Instead, think about it like this:
The shaded area is the area of the square (6 * 6) minus the area of the quarter circle.
Yeah iv found the area in the square. Then the area in the circle . Then taken them away to be left with the four parts, one of them being the shaded region so I divided by 4?
Yeah iv found the area in the square. Then the area in the circle . Then taken them away to be left with the four parts, one of them being the shaded region so I divided by 4?
Well, you could do that, but you haven't done the subtraction properly.
144−36π=108π. Instead, 144−36π is as simplified as possible (bar factorisation).