A word which means that the existence of one thing does not mean another thing cannot also exist

Question

For Example,

Solution A already exists, however it is a poor solution. We created solution B. The existence of B however, does not _____ the existence of A.

I was thinking preclude, however I thought that given that A already exists, this wouldn't fit. Thoughts?

Edit:

To be clear, what I mean is that both are allowed to exist at the same time. ie. The existence of B doesn't mean A can't exist and be used.

I thought I might be able to use: The existence of B does not preclude the existence of A.

However, I'm unsure if this is correct.

Answer 1

Negate:

• to deny the existence, evidence, or truth of: an investigation tending to negate any supernatural influences.
  
• to nullify or cause to be ineffective: Progress on the study has been negated by the lack of funds.

So, "The existence of B however, does not negate the existence of A."

Answer 2

In the sentence you offered, "invalidate" jumps out as a possible choice.However, 'preclude' is also an excellent choice.

The reasons one might choose one word over another are as follows:

Preclude comes from the Latin praecludere, praeclusum; where prae means 'before' + claudere means 'to shut'. which implies a temporal aspect to the data. With preclude, you are stopping something ahead of time.

Invalidate is derived from 'in' (the negation of) + valid and valid comes from the Frech invalide, which comes from the Latin invalidus = infirm or weak

Therefore, invalidate means:

1. Of no force, weight, or cogency; not valid; weak.

The word roots and definitions come from The Collaborative International Dictionary of English v.0.48 I hope this helps.