The area of the square is:
[tex]\begin{gathered} As=6^2 \\ As=36in^2 \end{gathered}[/tex]And the area of the circle is:
[tex]\begin{gathered} Ac=\pi r^2 \\ Ac=\pi\cdot(3\sqrt[]{2})^2 \\ Ac=18\pi \end{gathered}[/tex]The area of one segment is given by:
[tex]\begin{gathered} A=\frac{Ac-As}{4} \\ A=\frac{18\pi-36}{4} \end{gathered}[/tex]