S7 edge how to check if your /system is protected?

I recently rooted my phone but I can't edit my /system and I can't change my /system to R/W. I actually posted a question a few days ago on how to change my /system to R/W and got a reply saying that my /system could be protected. So how do I check if my /system is protected? If so how do I remove the protection?

from Android Forums at AndroidCentral.com - Ask a Question //forums.androidcentral.com/ask-question/757996-s7-edge-how-check-if-your-system-protected-new-post.html
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