Respuesta :
Answer:
This is already in its simplest form, but if you set the equation equal to zero, it's (x-3)(x+3).
Step-by-step explanation:
x^2-9=0
a= 1
b=0
c=-9
Factors of c (-9) that add up to make b (0): -3, 3
(x-3)(x+3)
we know: [tex]a^2-b^2=(a+b)(a-b)[/tex]
So: [tex]x^{2} -9=x^{2} -3^2=(x+3)(x-3)[/tex]
Ok done. Thank to me :>