Your answer is 100ft. This is because to find the radius when you already know the diameter you have to divide the diameter by 2.
Answer:
I believe it could be any number because:
let y=any number
x^2+10x+y=16+y
x^2+10x+y-y=16+y-y
x^2+10x=16
you can add any number to both side and not change the solution.
Area of the polygon = multiply all sides
10 * 5 * 4 * 3 * 4 * 3 * 5 = 36000in^2
Answer = 36000in^2