"how do I solve this equation 2-5[(-10)/(-5)*2-35] "
The method is to start with the INNERMOST brackets and work outwards from there:
[(-10)/(-5)*2 -35] = [(+2)*2-35] = [-31]
and now substitute in the remainder of your sum:
2 - 5*[-31] = 2 + 5*31 = 157
