Can't delete Dropbox installer from MacBook desktop

Hey everyone,

Having a bit of trouble deleting the dropbox installer after downloading the app onto my Macbook. (I cannot drag it into the trash or press the eject button without an error message popping up)

The first time around, I thought it was just an installation error on my part, so I went through the entire process of re downloading the installer and setting it up all over again. Now I have 'Dropbox Installer', 'Dropbox Installer 1', and 'Dropbox Installer 2' all lined up on my desktop. My assumption is that the installers can be deleted after a successful installation of the app.

The problem is, I cannot eject any of the installers because I keep getting the message that the Finder is still using it (even though I am not aware of this being the case). I went through the whole "go to the activity monitor and force quit the app" process. Every other forum page gives explanations on how to uninstall the app, which is not what I want either. I just want to get rid of the three dropbox installers on my desktop 😞 

Please help a confused soul, thank you!