Question

(x^{2} -y^{2})-(x^{2}+y^{2})=

Answer 1

hey buddy ,
ur answer is here:
(x^2-y^2)-(x^2+y^2)
=x^2-y^2-x^2-y^2
=-y^2-y^2
=-2y^2

hope it help u

Answer 2

ANSWER WITH FULL EXPLANATION
$( x^{2} - y^{2} ) - ( x^{2} + y^{2} )$
$= x^{2} - y^{2} - x^{2} - y^{2}$     [Opening the brackets]
$= x^{2} - x^{2} - y^{2} - y^{2}$     [Arranging the like terms together]
$= 0 - 2y^{2}$                               [Adding the like terms together]
$= -2y^{2}$                                   [Simplifying]

Here is you answer. 

Hope this may help you.