SOLUTION: A rectangular field will be fenced on all four sides. Fencing for the north and south sides costs $9 per foot and fencing for the other two sides costs $8 per foot. What is the max

Question 829718: A rectangular field will be fenced on all four sides. Fencing for the north and south sides costs $9 per foot and fencing for the other two sides costs $8 per foot. What is the maximum area that can be enclosed for $4800?
Answer by josmiceli(19441) (Show Source): You can put this solution on YOUR website!
Let = area of the field
Let = length of the field
Let = the width of the field

----------------------
I can say;

and substitute

Multiply both sides by

--------------------------------
This is a parabola with a maximum at where

and since

ft2
check answer:

The error is due to rounding off

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