So,
We know the formula for the area of a circle is:
[tex]A=\pi r^2[/tex]
All we have to do is to substitute the given value and simplify.
[tex]A=\pi (12)^2[/tex]
[tex]A=\pi (144)\ or\ 144\pi[/tex]
In numerical form, it would be 452.389342 or approximately 452.4 in.²