Answer:
a) 6
Step-by-step explanation:
Expanding the polynomial using the formula:

Also

I think you mean 
We can deduce that this term will be located somewhere in the middle. So I will calculate
.
For 

Note that we actually don't need to do all this process. There's no necessity to calculate the binomial, just 
For 

Product of a number and four is 4x
<span>12 more than that is 12+4x </span>
<span>fewer than 60 </span>
<span>12 + 4x < 60</span>
Add up all sides lengths:
s+6 + s+6 + s + s + 2s = 102
solve for s:
6s + 12 = 102
6s = 90
s= 15
The lengths of sides are as follows:
15, 21, 21, 15, 30 inches
I hope that
helps!
Answer: B) 
C) 
Step-by-step explanation:



Thus, Option B and C is giving the result 4b,
Therefore, they are the expressions that are equivalent to 4b.