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1 vote
1 vote
Suppose you are fencing a rectangular dog pen. The pen is to be 15 feet long and 7 feet wide. How much fencing would you need?

Please I really do need the answer I’ll mark you as brainlie

User Frankgreco
by
2.9k points

2 Answers

19 votes
19 votes

Answer:

Step-by-step explain to solve for the maximum area, the first derivative should be solved and equate it to zero, then solve for x.

A = 37x - x^2

dA / dx = 37 - 2x

equate dA / dx = 0

0 = 37 - 2x

2x = 37

x = 37 / 2

x = 18.5 ft

so the maximum area is

A = 37x - x^2

A = 37( 18.5) - 18.5^2

A = 342.25 sq ft

so the answer is letter B

User Sumsuddin Shojib
by
2.8k points
23 votes
23 votes

Answer:

44 feet

Explanation:

15 + 15 + 7 + 7 = 44

We can take all 4 sides and add them together to find the perimeter (aka how much fencing you need)

hope this helps :)

User DanielMason
by
1.7k points