Yes, I was Bao Dur, I know the equation, I figured it out quickly as well.
I didn't find the hidden tomb on Korriban though...
Also, according to PEMDAS order of operations, addition happens before subtraction so the equation would actually be
(12) - (8 + 9) / 1 = -5
(12) - (8 + 9) * 1 = -5
because you subtract last.
right?
just saying...,