What is the difference if the negative sign is inside or outside of the brackets in algebra?

If the negative sign is inside the brackets, for example: [-2(9)] it is a negative two and you times that by positive nine. But if it were -[2(9)] than you times two by nine and get eighteen, THEN the eighteen takes on the negative. So basically, if the negative sign is inside the bracket, then it will only affect the number it is closest to, but if it is outside the brackets, it affects all over the numbers inside of it.