What is the area of a regular 11-gon with a perimeter of 385 ft?

If its perimeter is 385 feet and it is an 11-gon then each side = 385 / 11 which equals 35 feet.
The area of a polygon = n * side^2 / (4 * tan (180 / n) where n = # of sides
area = (11 * 35^2) / (4 * tan (180/11))
area = 13,475 / (4 * 0.29363)
area = 13,475 / 1.17452
area = 11,472.77

Source:
http://www.1728.org/polygon.htm