Answer:
(a) 
(b) Domain:
<em>(See attachment for graph)</em>
(c) 
Step-by-step explanation:
Given



Solving (a): A function; l in terms of w
All we need to do is make l the subject in 
Divide through by 2

Subtract w from both sides


Reorder

Solving (b): The graph
In (a), we have:

Since l and w are the dimensions of the fence, they can't be less than 1
So, the domain of the function can be 
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To check this
When 



When 


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<em>See attachment for graph</em>
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Solving (c): Write l as a function 
In (a), we have:

Writing l as a function, we have:

Substitute
for l in 
becomes

As shown in the figures given :
For Figure 1 : perimeter = 8 units [As can be seen in the figure]
For figure 2(with 2 octagons) : perimeter = 8 × 2 - 1 = 15 units [since 1 side is common ]
For figure 2(with 3 octagons) : perimeter = 8 × 3 - 2 = 22 units [since 2 sides is common ]
If one more octagon is added
then perimeter = 8 × 4 - 3 = 29 units [since 3 sides will be common ]
I believe it’s D not 100% sure but yea
The answer is $37,923
<span>y = 844.697x^2 + 3723.485x - 13,650
x - number of years
y - the annual profit
If x = 8, the annual profit y is:
y = </span>844.697 * 8^2 + 3723.485 * 8 - 13,650
y = 844.697 * 64 + 29,787.88 - 13,650
y = 54,060.608 + 16,137.88
y = 37,922.728 ≈ 37,923