I know how to do a basic mouseover and how to do a mouseover where the change happens in another location, but how do you go about making two images change with one mouseover?

For instance I have ten square being used as a nav bar and I would like the following to happen when the mouse goes over the square...

I would like the square itself to change plus in another area of the page I would like an image to change to give a description of what that link does... (this change is immediately following the ten squares)...

is there an easy way to do this?