I'm trying to create an equation that, on occation, will result in a
subtraction of a negative, which then results in a larger negative number
than it should be.

So for example:

=sum(A1 - B1)
A1 = -50
B1 = 40

so the results of this equation is -90, but in reality it should be -10.

seems simple but it's confusing the hell out of me.

thanks in advance for the help.
roger