Q: "Other" Storage Takes Up 100+ GB? (El Capitan)

Hello,

Recently, I began getting messages on my 126GB Macbook Air warning me about a lack of available storage. This confused me, as I had purchased the device fairly recently (4-5 months ago) and had installed very little in that time. To figure out this issue, I looked at the "Disk Utility" application to find out what was taking up so much space, and found this:

As you can see, the majority of my space is taken up by something called "Other", while the rest of my files are not taking up much space at all. I have tried a few ways (specifically steps #1-7 on this article: https://www.igeeksblog.com/what-is-other-on-mac-how-to-remove/ )to identify just what is taking up this space, but have not been able to resolve it yet.

One theory I have about this relates to something I did within the first month of having the laptop, during which I followed an article from HowToGeek.com (http://www.howtogeek.com/213396/how-to-boot-a-linux-live-usb-drive-on-your-mac/) to install a flavor of Linux on my device. I believe I only partitioned a very small amount of my hard drive (5-15GB), so I don't know if this could have anything to do with the problem.

Are there any other courses of action I could take to fix this? I can provide more info if necessary.

I'm an OSX newbie, so sorry if this is an easy fix.