Hello there!
This circle is inscribed in this square meaning the diameter of the circle is the same as one of the square's sides.
We first need to find the area of the square...
base•height=area
10(10)=100
The area of the square is 100cm^2
Now let's find the area of the circle.
area=πr²
The radius is 5 because the diameter is 10...
π(5)^2
25π
78.5cm^2 is the approximate area of this circle.
The only thing left to do now is subtract 78.5 from 100 to get the area of the shaded region...
100-78.5=21.5
DON'T forget your units though!
21.5cm^2
I really hope this helps!
Best wishes :)