I very worried that the stray cat could have rabbies and if were to bite my dog she would get them to. And I don't want her to get scratched but I also don't want my anger towards the cat to act up (I would probably try to kill the cat)

Is your dog up to date on the rabies shot?

First, before assuming the feral cat has rabies.. check to see if it has they typical symptoms of rabies. If the cat does have rabies, I would think it would be your civic duty to call animal control/police to report that an animal in a residential neighborhood has a possibility of rabies.

Is your dog up to day with rabies? If not, I would suggest you get your dog up to date asap.

To eliminate all problems, call animal control and have them come trap the cat.. or.. trap the cat yourself and take it to the shelter.

Typically, a cat will not challenge a dog. A dog may corner it and scare the poop out of it, and naturally, the cat will defend itself.. but to worry that there is going to be a brawl under your deck.. highly unlikely.

Here is a link that describes what rabies is and the early symptoms.

Early Signs of Rabies in Cats (http://www.cathealthcareguide.com/rabies-in-cats.php)