[stared]

Linear algebra is simple (but ubiquitous - so you need to feel it, not only "sort of follow it").

Some visual matrix operations are here: http://setosa.io/ev/ If you want a beginner textbook, I recommend http://www.matrixanalysis.com/

Again, it is simple, so maybe you can even take course and look up Wikipedia when needed (but for me it is hard to guess you level, current knowledge, etc).

In any case, this ML course assumes some ML knowledge.

[vowelless]

I like this writeup: http://betterexplained.com/articles/linear-algebra-guide/

[magicmu]

Yeah, your last suggestion was what I was leaning towards. Because of the ubiquity of linear algebra, though, this seems like as good a time as any to start getting a good handle on it. Thanks for the resources!