Explanation
The area of a circle is given by the formula \( A = {\pi}r^2 \) where r is the radius of the circle. The radius of a circle is its diameter divided by two so:
\(r = \frac{d}{2} = \frac{18}{2} = 9\)
By definition, π is approximately 3.14 so:
\(A = {\pi}r^2 = 3.14 \times 9^2 = 3.14 \times 81 = 254.47\)