Quote: "MDAS means the order of operation which starts with Multiply, Divide, ADD, and then Subtract. "
That's a great rule, except that Divide comes before multiply. I was taught BODMAS (Brackets, order(?), divide, multiply, add, subtract).
I highly recommend TDKs tutorials. They're for DBC, but the principles are pretty much the same, and everything is brilliantly explained. The links in his sig if you can find one of his posts. He mostly posts in Dark Basic Chat and Newcomers, I think.
The hardest maths you'll ever have to use really is trig or vectors. They're not as hard as they first seem. Most maths will be done internally, so you won't actually have to do it, just know what it does.
Writing in DB is about as close to english as a programming language can get, but it still takes time to make something really good.
Good luck with learning it.