[tex]\boxed{\boxed{\pink{\sf Option \ A \ is \ correct .}}}[/tex]
Given function to us is :-
[tex]\bf \implies g(x) = x^2 - 9 [/tex]
And we , need to write the function a a product of linear factor by grouping or using the x method or a combination of both . So let's factorise this ,
[tex]\bf \implies g(x) = x^2 - 9 \\\\\bf\implies g(x) = x^2-3^2\\\\\bf\implies \boxed{\red{\bf g(x) = (x+3)(x-3) }}\:\:\bigg\lgroup \blue{\tt Using \ (a+b)(a-b) \ = a^2-b^2 }\bigg\rgroup [/tex]
I have also attached the graph of x²-9.
