The books I have seen they only go into to process of solving equations and matrices but they don’t offer theorems behind them.
I have studied Gilbert Strang’s linear algebra not all of it. What I studied from there I did not see any theorems, in case I missed.
Now my linear algebra course in college has theorems. I have notes but I need something to study a bit in detail to make sense of arguments. So I would really appreciate if someone can suggest anything.