If a-b=119 and a-b=7, what is the value of a?

I’m assuming one of those is supposed to be a plus? As you’ve got it written, there is no solution. If one of them is a plus, though, then you can add the two equations, solving for expressions style, and the *b*‘s will cancel. You’ll be left with 2*a* = 126, which means *a* = 63.