Question

i may have got the wrong end of the stick here, but I have little idea: A small goat is tethered by a rope to a point at ground level on a side of a square barn which
stands in a large horizontal field of grass. The sides of the barn are of length 2a and the rope
is of length 4a. Let A be the area of the grass that the goat can graze. Prove that A =/< 14 pi a^2
and determine the minimum value of A.