12 + 6x + 6x + 6y = 12 + 12x + 6y
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

Take out the factor of 3 from both numbers
(69)/3 = 23
(12)/3 = 4
69 + 12 can be rewritten as 3(23 + 4)
~
Answer:
16
Step-by-step explanation:
Let's represent this with an equation, where x is the first number. The next number must be x+2, because it has to be even, not x+1, and the rest continue the same way:
x+(x+2)+(x+4)+(x+6)+(x+8) = 100
Solve for x.
5x+20 = 100
5x = 80
<u>x = 16</u>