Answer:

And we can complete the squares like this:

And we got:

And we have a circle with radius r =3 and the vertex would be;

The graph is on the figure attached.
Explanation:
For this case we have the following expression:

And we can complete the squares like this:

And we got:

And we have a circle with radius r =3 and the vertex would be;

The graph is on the figure attached.