CPM Homework Help : INT3 Problem 3-66

What are the $x$ - and $y$ -intercepts and the vertex of $y=x^2+2x-80$ ? Sketch the graph and write the equation in graphing form.

Hint:

Set $x=0$ to determine the $y$ -intercept.

Let $y=0$ and then factor and use the Zero Product Property to solve for the $x$ -intercepts.

The vertex is $h$ and $k$ when the equation is in graphing form.

Answer:

$y=(x+1)^2−81$

Upward parabola, vertex at (negative 1, comma negative 81).