Chapter 11 - Section 11.5 - Quadratic Functions and Their Graphs - Practice - Page 809: 21

Please see the graph.

$g(x) = -x^2$ Axis of symmetry: $g(x) = -x^2$ $g(x) = -(x-0)^2$ $x=0$ Vertex: $g(x) = -x^2$ $g(0) = -0^2$ $g(0)= -0$ $g(0)=0$ The red line is the function $g(x) = -x^2$, the dot at $(0,0)$ is the vertex, and the orange line at $x=0$ is the axis of symmetry.