Answer:
![(m^2+n^2)/((m-n)(m+n))](https://img.qammunity.org/2019/formulas/mathematics/middle-school/vkdk0wz89owcathhzi8qp1lo26qg3w69wh.png)
Explanation:
Before we can subtract the fractions we require them to have a common denominator.
the common denominator is (m - n)(m + n)
multiply the numerator/denominator of the first fraction by (m + n) and
multiply the numerator/denominator of the second fraction by (m - n)
=
-
![(n(m-n))/((m-n)(m+n))](https://img.qammunity.org/2019/formulas/mathematics/middle-school/qguw835n0id7yhit8tznna195d6h2tkizl.png)
distribute and simplify the numerators
=
![(m^2+mn-mn+n^2)/((m-n)(m+n))](https://img.qammunity.org/2019/formulas/mathematics/middle-school/suuoiwpv03qkm5wqaukdck7lkpyue7i188.png)
=
![(m^2+n^2)/((m-n)(m+n))](https://img.qammunity.org/2019/formulas/mathematics/middle-school/vkdk0wz89owcathhzi8qp1lo26qg3w69wh.png)