Thank you Lindy for the quick response to my question. After reading your response I went back and looked at the problems closely and found that the negative and positive number signs were just slightly raised (almost non-detectable) so therefore I will go back and braille them as left superscripts. Also, in knowing that standardized test handle these numbers as superscripts is good information that will help me in the future when this situation comes up.
Thanks again for your help!!!