Find the dimensions of the rectangular corral split into 2 pens of the same size producing the greatest possible enclosed area given 200 feet of fencing

Corral dimensions:

x = 50 ft

y = 33,33 ft

A(max) = 1666,5 ft²

A(pen) = 833,25 ft²

Step-by-step explanation:

Let´s call  "x" and  "y" dimensions of the corral

Then the perimeter is:

p = 2*x + 2*y , and in order to get two pens of equal dimensions we need to split by the use of other length y then

p = 2*x + 3*y = 200

y = (200 - 2*x)/3

Area of the corral

A(c) = x*y

Area as function of x is:

A(x) = x * ( 200 - 2*x)/3

A(x) = (200*x - 2*x²)/3

A(x) = (200/3)*x - (2/3)*x²

Taking derivatives on both sides of the equation:

A´(x) = 200/3 - (4/3)*x

A´(x) =  0     200/3 - (4/3)*x = 0   ⇒  200 - 4*x = 0

x = 50 ft.

y = ( 200 - 100)/3

y = 100/3

y = 33,33 ft  

A(max) = 33,33*50

A(max) = 1666,5 ft²

Area of each pen

A₂ = 833,25 ft²

answer: c.  

step-by-step explanation:

mixtures containing substances that get attracted to magnet can be separated using a magnet. we can separate iron from a mixture of sand and iron, as only iron attracts to the magnet.