Am I going to lose my data on my Mac partition if I delete the Linux partition to extend my Mac partition? I have a MacBook Pro with two partitions:


macOS partition (200 GB). 
Linux partition (100 GB).


When I enter the Recovery Mode and open Disk Utility, and click "partition" on my whole HD device, I can see a pie chart showing each partition and its size. 

My goal is to delete the Linux partition and get back to the normal state where my Mac has a full 300 GB of storage instead of 200 GB. 

My question is:
If on the pie chart I clicked on the Linux partition and clicked the minus "-" symbol, will it achieve my goal?

Is it going to delete my Linux partition and give its size to the Mac without losing any data on my Mac partition?
The answer is no you will not lose your data.

You now are a potential member in the "Unintended Consequences" club. So what we do here is change "no" to "you probably won't lose data if everything goes well."

Which means, backup the entire Mac partition and then boot from the backup and make sure it is good before proceeding.

Once you have your backup that Murphy's Law of Unnecessary Backups says you will now never need the backup you just made, you may now proceed with deleting the Linux partition and expanding the macOS partition into the empty space. Which is not supposed to delete anything on your macOS partition, if everything goes well.