SOLUTION: Expand the binomial: (3-y)^3

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Question 46738: Expand the binomial: (3-y)^3
Found 2 solutions by consc198, ikleyn:
Answer by consc198(59) About Me  (Show Source):
You can put this solution on YOUR website!
The answer is 27 because 3 x 3=9
9 x 3=27

Answer by ikleyn(53828) About Me  (Show Source):
You can put this solution on YOUR website!
.
Expand the binomial: (3-y)^3
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        The "solution" in the post by @consc198 has nothing in common with the truth.
        For correct solution, see my post below. 

As you are going to expand the binomial, you should know, as a prerequisite,
this expanding formula for binomials of degree 3


    %28a%2Bb%29%5E3 = a%5E3 + 3a%5E2%2Ab + 3ab%5E2 + b%5E3. 


To get the required expanding, plug in here a = 3,  b = -y.  You will get


    %283-y%29%5E3 = 3%5E3 - 3%2A3%5E2%2Ay + 3%2A3%2Ay%5E2 - y%5E3 = 27 - 27y + 9y%5E2 - y%5E3.     ANSWER

Solved correctly.