Answer:
The answer I think would be hexagon
A. f(b) = 3+b
b. f(x) = (x+3)²
c. f(x) = (x+3)/(12-x)
d. f(x) = x⁵-4x+6
e. f(x) = -45
f. f(x) = x
I think this is what you want to do
Your welcome
The simplified form of the expression is 
<h3>Simplifying an expression</h3>
From the question, we are to simplify the given expression
The given expression is

The expression can be simplified as shown below





Then,





Hence, the simplified form of the expression is 
Learn more on Simplifying an expression here: brainly.com/question/2320607
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