Respuesta :

apologiabiology
factour ouf 3
f(x)=3(x²-9)
recognize diference of  2 perfect squres

a²-b²=(a+b)(a-b)
x²-9=x²-3²=(x+3)(x-3)

so
f(x)=3(x+3)(x-3)
seto to zero to find roots
0=3(x+3)(x-3)

0=x+3
-3=x

0=x-3
3=x

roots at x=-3 and 3

Otras preguntas