SOLUTION: factoring a harder difference of two squares: (x-3)^2 - 4z^2 i dont know how to factor this

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Question 237808: factoring a harder difference of two squares:
(x-3)^2 - 4z^2
i dont know how to factor this
Answer by solver91311(24713) About Me  (Show Source):
You can put this solution on YOUR website!


Perhaps it will be easier to see if you use a substitution.

Let . Then we can say

Let . Then we can say

Now, we know that:



So just do the substitutions:



Why didn't I worry about the negative square root when I was defining and ? Think about it -- if we had defined , for example, as , then the above would just have come out:




That is to say, same answer.

John