Respuesta :

1-9a^2
1-(3a)^2
1^2-(3a)^2  ----------(a^2-b^2)=(a+b)(a-b)
(1+3a)(1-3a)
SyntaxError
[tex](1-9a^2)\\ (1-3a)(1+3a)[/tex]

Whenever we have a perfect squared and a variable to the power of 2 being subtracted we can always factor it into two separate quantities.