Solution a is less than b is less than 0 and less than c, /a/ greater than /b/ greater than /c/

That is, a+b < 0, a-c-b>0, b < 0, c-b>0.

:/a+b/-/a-c/-/b/-/c-b/

=-a-b-(-(a-c))-(-b)-(c-b)

=-a-b+a-c+b-c+b

=b-2c