I believe it is an imaginary number because imaginary numbers are square roots of negative numbers.
Answer:
What do you exactly need to do?
Step-by-step explanation:
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

Answer: D) Reflect over x-axis
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Explanation:
When we do this type of reflection, a point like (1,2) moves to (1,-2).
As another example, something like (5,-7) moves to (5,7)
The x coordinate stays the same but the y coordinate flips in sign from positive to negative, or vice versa.
We can say that
as a general way to represent the transformation. Note how y = f(x), so when we make f(x) negative, then we're really making y negative.
If we apply this transformation to every point on f(x), then it will flip the f(x) curve over the horizontal x axis.
There's an example below in the graph. The point A(2,8) moves to B(2,-8) after applying that reflection rule.