Given a quadratic equation of the form:
[tex]f(x)=ax^2+bx+c[/tex]
The equation of the axis of symmetry is obtained using the formula:
[tex]x=-\frac{b}{2a}[/tex]
From the given quadratic equation:
[tex]\begin{gathered} g\mleft(x\mright)=x^2+4x+3 \\ a=1 \\ b=4 \end{gathered}[/tex]
Therefore, the equation of the axis of symmetry of g(x) is:
[tex]\begin{gathered} x=-\frac{4}{2\times1} \\ x=-2 \end{gathered}[/tex]
The correct option is B.
