How do you insert parentheses, operation signs, and exponents to make -2 8 3 = -8 true?
I'm sure that there's more than one way to do it, but here's the easiest.
First, I try to get rid of everything except the 8. I make -2 and 3 equal to 1 by raising them to the power of zero. I subtract one from the other so that they cancel. And then, I just put a negative sign in front of the 8.