/sci/ - Science & Math

I tried asking this on /g/ and failed horrible.

I've been playing with my Arduino and some lego blocks all day, setting up LCD screen, distance sensor, the ethernet shield, it's fun. But the moment I have to deal with some thing more complex, something that requires resistors n' stuff, I'm completely lost.

Could any anons well versed in the language of magical pixies suggest to me some resources for learning from scratch?

I really want to have a decent understanding of how electricity behaves.

I had a math test.On the test it said to factor 25 x. how do I do this? I personally think it is impossible. And yes that is a space between 25 and x.