The 1st conjugation and 9th conjugation both end in "ać"

Okay, so while flipping through my dictionary, I find that in Polish the 1st conjugation and 9th conjugation both end in "ać", but there is no explanation as to when to use each of the conjugations.

Example: 1st, czytać; 9th, wiązać

So, how would I determine (at first glance) which is the proper conjugation?

"301 Polish Verbs - completely conjugated" by Barron's is by far the best guide to any and all questions regarding Polish conjugation etc.. for Anglo-Saxon native speakers-:)

From wiktionary.org/wiki/Aneks:Język_polski_-_koniugacja_IX.

In 9th conjugation, verbs change in stem: z → ż, s → sz or r → rz.
In the 1st, not.

Conjugations can be tricky, particularly with some of those nasty stem-changing ones, e.g.
"ciąć" (to cut): tnę, tniesz, tnie etc.... not to mention the irregular past tense forms, depending upon the numbering system of what is being cut, for instance.

The Barron's book, along with Brook's Polish Reference Grammar made it quite clear to me, FINALLY!