Find the dimensions of the rectangular corral producing the greatest enclosed area given 320 feet of fencing. (Assume that the length is greater than or equal to the width.)

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Answer:

The dimensions of the rectangular corral producing the greatest enclosed area  is a square of 80 ft x 80 ft

Step-by-step explanation:

Let

x -----> the length of the rectangular corral in feet

y -----> the width of the rectangular corral in feet

we know that

The area of the rectangular corral is equal to

[tex]A=xy[/tex] -----> equation A

The perimeter of the rectangular corral is equal to

[tex]P=2(x+y)[/tex]

[tex]P=320\ ft[/tex]

so

[tex]320=2(x+y)[/tex]

Simplify

[tex]160=(x+y)[/tex]

[tex]y=160-x[/tex] -----> equation B

substitute equation B in equation A

[tex]A=x(160-x)[/tex]

[tex]A=-x^2+160x[/tex]

This is a vertical parabola open downward

The vertex is a maximum

The x-coordinate of the vertex represent the length for the maximum area

The y-coordinate of the vertex represent the maximum area

Convert the quadratic equation in vertex form

[tex]A=-x^2+160x[/tex]

Factor -1

[tex]A=-(x^2-160x)[/tex]

Complete the square

[tex]A=-(x^2-160x+80^2)+80^2[/tex]

[tex]A=-(x^2-160x+80^2)+6,400[/tex]

Rewrite as perfect squares

[tex]A=-(x-80)^2+6,400[/tex]

The vertex is the point (80,6,400)

so

[tex]x=80\ ft[/tex]

The maximum area is 6,400 ft^2

Find the value of y

[tex]y=160-x[/tex]  ----> [tex]y=160-80=80\ ft[/tex]

therefore

The dimensions of the rectangular corral producing the greatest enclosed area  is a square of 80 ft x 80 ft

The dimension of the rectangular corral is 80 by 80 feet. when the length is equal to the width.

What is a rectangle?

It is a polygon that has four sides. The sum of the internal angle is 360 degrees. In a rectangle, opposite sides are parallel and equal and each angle is 90 degrees. And its diagonals are also equal and intersect at mid-point.

The perimeter of the rectangle is 320 feet.

Let L be the length and W be the width of the rectangle.

Assume that the length is greater than or equal to the width. Then

[tex]\rm L \geq W[/tex]

Then we have, the perimeter of the rectangle is given as

[tex]\rm Perimeter = 2( Length + Width)\\[/tex]

Then

[tex]\rm 2(L+W) = 320\\\\L \ \ + \ \ W = 160[/tex]

Let L = W, then

[tex]\rm W = 80[/tex]

Thus, the dimension of the rectangular corral is 80 by 80 feet.

More about the rectangle link is given below.

https://brainly.com/question/10046743