Answer:
First Box: Factor by difference of squares
Second Box: It has all perfect squares
Third Box: see my work
Step-by-step explanation:
We have the equation 
Before we do anything, let us bring all of the terms to the left side

Now that we have moved the terms to one side, it is clear that we have a difference of squares.
-Work-

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B is correct
12/3=4
-> 3 x 4 = 12
Answer:
5mph
Step-by-step explanation:
Let speed of boat in still water is s.
Distance proportional to speed
90/10 = (s+ 4)/(s - 4)
=> 9s - 36 = s + 4
=> 8s = 40
=> s= 5 mph
:-)
Answer:
LETTER A
Step-by-step explanation:
I think it's correct