Question

subtract :
(a+b) - (a-b)

Answer 1

(a+b)-(a-b)
=a+b-a+b
=2b.........[as a nd a got cancel up.

Answer 2

(a+b ) - ( a - b )

a  +  b
a  -  b
---------
   + 2b
----------

so the answer is 2b.......