Answer:
I guess that the shaded area is a quarter of a circle of radius 12 units.
Is easy to know that the area, will be equal to the quotient between the area of a circle of radius 12, and 4
We know that the area of a circle of radius R is:
A = pi*R^2
in this case, R = 12
pi = 3.14
Then:
A = 3.14*12^2 = 452.16
And a fourth of that is:
A/4 = (452.16)/4 = 113.04
The area of the shaded region is 113.04 square units
