SOLUTION: Well, I have a math problem that say," Yoy have 180 feet of fence to make a rectangular pen. One side of the pen will be against a 200 foot wall, so it requires no fence. What are

Question 447227: Well, I have a math problem that say," Yoy have 180 feet of fence to make a rectangular pen. One side of the pen will be against a 200 foot wall, so it requires no fence. What are the dimensions of the rectangle with the maximum area?" and i would like for you to help me on it.
Answer by ankor@dixie-net.com(22740) (Show Source): You can put this solution on YOUR website!
You have 180 feet of fence to make a rectangular pen.
One side of the pen will be against a 200 foot wall, so it requires no fence.
What are the dimensions of the rectangle with the maximum area?"
:
The perimeter equation for a 3 sided pen
L + 2W = 180
L = (180-2W)
:
The area equation:
A = L*W
replace L with (180-2W)
A = W(180-2W)
A = -2W^2 + 180W
Max area occurs at the axis of symmetry, formula for that: x=-b/(2*a)
In this equation
W =
W =
W = +45 ft is the width for the max area
Find the Length
L = 180 - 2(45)
L = 180 - 90
L = 90 ft is the length for max area
:
Actual area 45*90 = 4050 sq/ft

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