Answer:
See below
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>
<em></em>
Solving (c): Write l as a function 
In (a), we have:

Writing l as a function, we have:

Substitute
for l in 
becomes

If R is between Q and S then QR+RS=QS
given
QR=x+4
RS=3x-1
and QS=27
x+4+3x-1=27
combine like terms
4x+3=27
minus 3 both sides
4x=24
divide both sides by 4
x=6
sub back
QR=x+4
QR=6+4
QR=10
RS=3x-1
RS=3(6)-1
RS=18-1
RS=17
x=6
QR=10
RS=17
Answer:
25
Step-by-step explanation:
(x-14)*-3 = -33
-3x+42 = -33
-3x = -33-42
-3x = -75
x=25