The formula for the area of a circle is \(A=\pi r x^{2}\)
The radius if half your diameter,
In this case your diameter is 12 so your radius is 6
Then you plug it in the equation, so it is A= \(\pi 6^{2}\) or A=36 \(\pi\)
This leaves you with the area at about 113.04 \(centimeters ^{2}\)