What is the largest possible area that Lemuel could enclose with the fence, if he wants to enclose a rectangular plot of land with 24 feet of fencing?

1 Answer
Mar 26, 2018

Largest possible area is 36 sq.ft with sides x=y=6 ft

Explanation:

Let the sides of rectangle is x and y

Perimeter of the rectangle is P=2(x+y)=24 or

P= (x+y)=12 :. y=12-x

Area of the rectangle is A=x*y= x(12-x) or

A= -x^2+12x = -(x^2-12x) or

A= -(x^2-12x+36)+36 or

A= -(x-6)^2+36 . square is non negative quantity.

Therefore to maximize A minimum should be deducted from

36; :. (x-6)^2=0 or x-6=0:. x=6:. A=36 So largest

possible area is 36 sq.ft with sides x=y=6 [Ans]