Answer:
The long fence, AC = 44 feet
4 shorter segments at 11feet each = 44 feet
Area = 484 ft^2
Step-by-step explanation:
The three pens will share one fence section parallel to the barn, we'll call it AB. Each pen will need two side fence segments, from the front fence to the barn. We'll call those portions AC. We need four of them: two for the outer sides and two more to divide up the space equally among the three pens. The total area would be AB*AC.
We know that AC + 4AB = 88 feet.
or AC = (88feet - 4AB)
Area = AB(88feet - 4AB)
Area = 88AB - 4AB^2
To maximize the area, we can take the first derivative and set it equal to zero:
Area' = 88 - 8AB
0 = 88 - 8AB
AB = 11 feet
AC = (88 - 4AB)
AC = (88 - 44)
AC = 44 feet
The fours segments of fence:
AC + 4AB = 88 feet
(44) + 4(11 feet) = 88feet
Area = 44' x 11 ft' = 484 ft^2