Upgraded my video card...now how do I run 2 monitors?

I just received our new HP Pavilion 500t in the mail today.  We need to run dual monitors, so per a chat conversation with an HP employee, we upgraded to the  "1GB Nvidia GeForce GT 705 [DVI, HDMI, DVI to VGA Dongle" graphics card. 

There is only one monitor port displayed on the back of the PC.  There are 2 other ports, but they are covered up with black pieces of plastic that say "Do not remove".

So....how do we hook up 2 monitors, which is why we upgraded to begin with.

Thanks in advance!