Given the function [math]f(x) = –2(x + 1)(x + 5)[/math], identify the key features of its graph: the extremum, vertex, [math]x[/math]-intercept(s), and [math]y[/math]-intercept. Then sketch the graph.
[list=1] [*]Determine the extremum of the graph. [*]Determine the [math]x[/math]-intercepts of the graph. [*]Determine the vertex of the graph. [*]Determine the [math]y[/math]-intercept of the graph. [*]Graph the function. [/list]