Monday

December 22, 2014

December 22, 2014

Posted by **April** on Thursday, March 10, 2011 at 1:16pm.

- Algebra and Trig -
**Reiny**, Thursday, March 10, 2011 at 1:45pmmissing info

how many feet of fencing?

Suppose he has 120 feet, change the solution below to the appropriate number of feet in your question

let length of field be y, (y being parallel to house.)

let the width be x

2x + y = 120

y = 120-2x

area = xy

= x(120-2x)

= 120x - 2x^2

If you are in Calculus .....

d(area)/dx = 120 - 4x = 0 for a max area

x = 30

y = 120-2(30) = 60

Max area = 30(60) = 1800 ft^2

if you don't take Calculus, complete the square

area = -2(x^2 - 60x +**900 - 900**)

= -2(x-30)^2 + 1800

max area is 1800, when x = 30

- Algebra and Trig -
**tchrwill**, Thursday, March 10, 2011 at 4:46pmConsidering all rectangles with a given perimeter, one side being another straight boundry, the 3 sided

rectangle enclosing the greatest area has a length to width ratio of 2:1.

**Answer this Question**

**Related Questions**

math - Kira has feet of fencing. She will use it to form three sides of a ...

Polynomials and quadratic application - I want to make a rectangular garden by ...

Maath:) - Sam is going to plant a rectangular flower garden next to his house. ...

College math/bus calc - A rectangular-shaped garden has one side along the side ...

math - dale have decided to fence off the garden plot behind his house, using ...

math - a rectangular garden with an area of 2112 square feet is to be located ...

algebra 1 - Charles wants to build a vegetable garden such that three sides of ...

college algebra - a rectangular lot whose perimeter is 440 feet is fenced along ...

word problem? - A rectangular lot is to be bounded by a fence on three sides adn...

Algebra - A gardener has 60 feet of fencing with which to enclose a garden ...