Posted by Anonymous on Sunday, February 1, 2009 at 8:54pm.
If Steve has 120 feet of fence to make a rectangular kennel and he will use his house on one side, how would the dimensions be found for a kennel with the greatest area be found?

Math  Damon, Sunday, February 1, 2009 at 9:06pm
L + 2 w = 120
A = L w
A = (120 2w)w = 120 w  2 w^2
that is parabola opening down, find the vertex (I assume you do not know calculus which would be easier)
2 w^2 + 120 w = A
complete square
w^2  60 w = A/2
w^2  60 w + 30^2 = A/2 + 900
(w30)^2 = A/2 + 900
so
w = 30
then L = 120  60 = 60

Math  bobpursley, Sunday, February 1, 2009 at 9:06pm
Area= LW
Perimeter= 2L+ W
dArea/dL= W + dW/dl
the last term you get from taking the derivative of the perimeter equation
0 (perimeter is constant)=2 + dW/dl
so put that in the darea/dl, set to zero, and solve for W.

Math  Anonymous, Sunday, February 1, 2009 at 9:13pm
Thanks
Answer This Question
Related Questions
 Math(Reiny Please Help)  Lacy has $600 set aside to build a rectangular ...
 Math2  Lacy has $600 set aside to build a rectangular exercise kennel for her ...
 Calc.  A dog kennel owner needs to build a dog run (rectangular area) adjacent ...
 Math  A dog kennel owner needs to build a dog run (rectangular area) adjacent ...
 math  the area of a dog kennel is 20 square feet. If the length of the kennel ...
 Basic college math  A rectangular kennel measures 26 1/2 feet by 20 1/4 feet. ...
 Math  A gardener has 120 ft of fencing to fence in a rectangular garden. one ...
 Data Management  A kennel is to be enclosed with a 20m of fencing. The length ...
 algebra  A gardener has 120 ft of fencing to fence in a rectangular garden. one...
 Algebra 2 b  Jane is going to fence in her back yard. She has purchased 100 ...
More Related Questions