Using multiple categories for a single article is better?

[Daffy10]

Hi, the question is: I have a website in worpdress and sometimes set more categories (max 2) to a single and unique article and creates this situation:

Ariticle-a which is visible on: website.com/category-1/article-a and website.com/category-2/article-a

It is okay for SEO or it would be better select just one category?

Thanks

[Ajinkya Samark]

Adding related categories are allowed for tagging. Should be relevant with article. Because tagging is working as Keywords when Google is giving ranking for your site.