Farmer and the dell
Farmer Johnson has some left over fencing after the harvest this fall. He has a nice neighbor who has already built a fence along the boundary of their two properties. Therefore farmer Johnson thinks he should utilize the common fence so he can maximize the area of the enclosure. If farmer Johnson only uses rectangles for pens and he has 400 ft of fencing left over. What is the width of the pen be?
The answer is 100.
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1 solution
Call the two lengths x and the long side (400-2x) Graph y= -2x^2+400x find the maximum and the x value is 100. Or you can place the parabola into vertex forrn and find the max from there.