express the area of the rectangle as a function of x

Question

a farmer has 7200 feet of fencing available to enclose a rectangular are and divide it into ten rectangular plots. let x represent the length of the side of the rectangle as defined in the figure shown

Answer 1

If the farmer has 7200 ft of fencing, it has to go all the way around the rectangle.  The rectangle has four sides, two "lengths" (L) and two "widths" (W).  The first thing we need to note is that 2W + 2 L = 7200.

 

If L = x (which I am assuming based on your description of the rectangle), then we can say 2W + 2x = 7200.  If we want to express the width in terms of x, we can solve for W.

 

2W + 2x = 7200    subtract 2x from both sides of the equation to get:

2W = 7200-2x   then divide both sides by 2 to get:

W = 3600-x

 

So now we have the outer dimensions of the rectangle in terms of x.  Length = x and Width = 3600-x

 

But without the picture of the smaller rectangles, we really can't go any further...  :(