Chapter 8 - Graphing Quadratic Functions - 8.4 - Graphing f(x) = a(x-h)^2 + k - Exercises - Page 447: 31

Vertex:$(-4,-3)$. Axis of symmetry: $x=-4$

The quadratic function in the form $y=a(x-h)^2+k$ has the vertex $(h,k)$ and the axis of symmetry $x=h$. Given: $$y=-6(x+4)^2-3$$ Rewrite as: $$y=-6(x-(-4)^2-3$$ Therefore $h=-4$, $k=-3$. The vertex is: $$(h,k)=(-4,-3).$$ The axis of symmetry is: $$x=-4.$$