Respuesta :

Answer:

The axis of symmetry is

[tex]x=-\frac{3}{2}[/tex]

Step-by-step explanation:

The given function is [tex]f(x)=3x^2+9x+15[/tex].

Compare to [tex]f(x)=ax^2+bx+c[/tex],

[tex]a=3,b=9,c=15[/tex]

The axis of symmetry of the parabola is given by the formula;

[tex]x=-\frac{b}{2a}[/tex]

We substitute into the formula to get;

[tex]x=-\frac{9}{2(3)}[/tex]

The axis of symmetry is

[tex]x=-\frac{3}{2}[/tex]