Math一問~~~~~

圖片參考：http://farm3.static.flickr.com/2358/2222222851_2dc98f2c79.jpg?v=0

Let the length is x width is y
Then the dimension of the football field is
length=(x-4)
width=(y-4)
So 2(x+y)=88...(1)
(x-4)(y-4)=xy*(2/3)...(2)
Expend (2)
xy-4(x+y)+16=xy*2/3
(xy/3)+16=4(x+y)=176
xy=480
x(44-x)=160
x^2-44x+160=0
(x-40)(x-4)=0
x=40 or 4
y=4 or 40
The dimensions of the piece of land is
length 40 width 4 or
length 4 width 40