The factored form of the expression [tex]x^2 - 9[/tex] is [tex](x+3)(x-3)[/tex]
The expression x^2 + 9 has no real roots hence cannot be factored
Quadratic equations are equations with a degree of 2.
Given the quadratic function [tex]x^2-9 \ and \ x^2+9[/tex]
For the function [tex]x^2 - 9[/tex]
[tex]=x^2-9\\=x^2-3^2[/tex]
Using the difference of two squares:
[tex]a^2-b^2=(a-b)(a+b)\\x^2-3^2=(x-3)(x+3)[/tex]
For the expression x^2 + 9
The expression x^2 + 9 has no real roots hence cannot be factored
Learn more on factorization here: https://brainly.com/question/20293447
