=

That's it. All there is to it.

=

That's the beauty of Natural Laws, you can mess with them all you want! You can add constants and variables and all kinds of cool stuff, with only one minor constraint, you need to hold true to =. Changing one side of a Natural Law (=) necessitates an appropriate modification to the other side in order to maintain it's Natural Law-ness identity. If you don't, it's now longer a Natural Law, and therefore is irrelavent to your question.

Therefore... =.

('though I have to admit that Traveling Girls answer is more fun)