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A rectangular garden will be fenced using 400 feet of fencing material. One side of the garden is partly covered by the barn and that part will not be fenced. If the barn is 50 feet long, what are the dimensions that will maximize the area of the garden? What is the largest possible area?

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Answer:

The dimensions that maximize the area of the garden are 200 feet by 100 feet.

The largest area for the garden would be 20,000 square feet

Explanation:

Let the length of the garden be x feet and the width be y feet. One side of the garden is adjacent to the barn, which is 50 feet long. Since only three sides need to be fenced, we can set up the following equation for the perimeter:

x + 2y = 400

We need to find the dimensions that will maximize the area of the garden, which is given by A = xy. First, we will express y in terms of x using the perimeter equation:

y = (400 - x) / 2

Now, substitute y in the area equation:

A(x) = x(400 - x) / 2

A(x) = (400x - x^2) / 2

To maximize the area, we need to find the critical points of the function A(x). We do this by taking the first derivative and setting it to 0:

A'(x) = (400 - 2x) / 2

A'(x) = 200 - x

Now, set A'(x) to 0 and solve for x:

200 - x = 0

x = 200

Now, substitute x = 200 back into the equation for y:

y = (400 - 200) / 2

y = 200 / 2

y = 100

So, the dimensions that maximize the area of the garden are x = 200 feet (length) and y = 100 feet (width). Now we can find the largest possible area:

A = xy

A = (200)(100)

A = 20,000 square feet

The largest possible area for the garden is 20,000 square feet.

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