we have that
the area of the shaded region is equal to the area of the complete square, minus the area of two semicircles (one circle)
so
step 1
Find out the area of the square
A=10^2
A=100 cm2
step 2
Find out the area of two semicircles or one circle
[tex]A=\pi\cdot r^2[/tex]
we have
pi=3.14
r=10/2=5 cm
substitute
[tex]\begin{gathered} A=3.14\cdot5^2 \\ A=78.5\text{ cm2} \end{gathered}[/tex]
step 3
the area of the shaded region is equal to
A=100-78.5
A=21.5 cm2
