(PLEASE HELP)
A farmer has 1800 feet of fence and wants to enclose a rectangular field with two internal fence parallel to one side, as shown below (drawn)
What are the dimensions that would maximize the area?
( I would appreciate just getting started on it and I can do the rest)

Question

(PLEASE HELP)
 A farmer has 1800 feet of fence and wants  to enclose a rectangular field with two internal fence parallel to one side, as shown below (drawn)
What are the dimensions that would maximize the area?
( I would appreciate just getting started on it and I can do the rest)

anonymous · Answer

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anonymous · Answer

A-area W*L        W=A/L
fencing 4W+2L=1800
            4A/L +2L=1800

mulptiply by L

4A+2L^2 =1800L

dA/dL=o for max/min  and solve

anonymous · Answer

dA/dL=4L-1800=0 for  max
L=1800/4=450
2L=900
4w=1800-900=900
w=900/4=225
so 
L=450
W=225

anonymous · Answer

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