Friday

November 21, 2014

November 21, 2014

Posted by **Mysty** on Thursday, May 19, 2011 at 1:13am.

- Algebra 2 -
**drwls**, Thursday, May 19, 2011 at 6:33amLet L be the length of fence parallel to the river.

A = L*(2400-L)/2 = 1200L - L^2/2

dA/dL = 0 = 1200 - L (using calculus)

L = 1200 m for maximum A

Amax = 1200*600 = 720,000 m^2

You can get the same answer by completing the square.

A = -(1/2)(L^2 -2400L + 1,440,000) + 720,000

= (-1/2)(L-1200)^2 + 720,000

That obviously has a maximum value when L = 1200.

**Answer this Question**

**Related Questions**

Applied Math- Gr.11 - A farmer wants to enclose three sides of a rectangular ...

math - A farmer with 2000 meters of fencing wants to enclose a rectangular plot ...

Algebra - A farmer plans to enclose a rectangular region using part of his barn ...

Math - A farmer with 8000 meters of fencing wants to enclose a rectangular plot ...

math - a farmer with 10,000 meters of fencing wants to enclose a rectangular ...

intermediate algebra - A farmer with 3000 feet of fencing wants to enclose a ...

calculus optimization problem - A farmer has 460 feet of fencing with which to ...

Math - A farmer uses 1034 meters of fencing to enclose a rectangular region and ...

Algebra - Word Problems: 1. A farmer has 2400 feet of fencing and wants to fence...

algebra - A farmer decides to enclose a rectangular garden, using the side of a ...