SOLUTION: My son is trying to learn how to factor when either square is a square of a polynomial. Such as this problem: 9a^2-(2a-5)^2. I know the answer from the teacher book is 5(a-1)(a+5)^

Question 262895: My son is trying to learn how to factor when either square is a square of a polynomial. Such as this problem: 9a^2-(2a-5)^2. I know the answer from the teacher book is 5(a-1)(a+5)^2, but I can't explain to him how to work it. Any help is appreciated.
Phebe Little, for my son Micah, who is in Algebra I
Answer by checkley77(12844) (Show Source): You can put this solution on YOUR website!
9a^2-(2a-5)^2
9a^2-(4a^2-20a+25)
9a^2-4a^2+20a-25
5a^2+20a-25
5(a^2+4a-5)
5(a-1)(a+5) ans.
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[5(a-1)(a+5)^2 NOT AN ANSWER.]
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