Question 1054244
 Cindy wants to construct five rectangular dog training areas side by side, using a total of 600 ft of fencing. What should the overall width and length be to maximize the area of the five combined areas? What are the dimensions of each individual arena? What's the area of each arena? 
----------------------
Sketch a rectangle that is wider than high.
Sketch in 4 vertical segments to create 5 equal-areas in the rectangle.
----------
You now have 6 vertical pieces plus a base and a top.
-----------------
Let each verticle be "x".
Each horizontal piece is (600-6x)/2 = 300-3x
-----------
Area = x(300-3x) = -3x^2 + 300x
----
Max occurs when x = -b/(2a) = -300/(2(-3)) = 50
----
Dimensions of each small area::
height = x = 50 ft
width = (300-3x)/5 = (300-3*50)/5 = (300-150)/5 = 30 ft
---
Each small area = 50 by 30 = 1500 sq ft.
------------
Cheers,
Stan H.