we have that
The area of the remaining board is equal to the area of the square minus the area of the circle
so
[tex]A=b^2-\pi r^2[/tex]
where
b=6 ft
r=6/2=3 ft ---------> the radius is half the diameter
pi=3.14
substitute
[tex]\begin{gathered} A=6^2-(3.14)(3)^2 \\ A=7.74\text{ ft}^2 \\ A=8\text{ ft}^2 \end{gathered}[/tex]
The area is 8 square feet
