For this case, we must factor the following expression:
[tex]x ^ 2-25[/tex]
By definition, by difference of percfect squares we have:
[tex](a ^ 2-b ^ 2) = (a + b) (a-b)[/tex]
Let:
[tex]a = x\\b = 5[/tex]
We have:
[tex]x ^ 2-25 = x ^ 2-5 ^ 2 = (x + 5) (x-5)[/tex]
Thus, the factored expression is:
[tex](x + 5) (x-5)[/tex]
Answer:
[tex](x + 5) (x-5)[/tex]
