Question 1006349
Putting into all positive exponents,
{{{(9-m^2/n^2)/(3-m/n)}}}


The lowest common denominator between the two parts is  {{{n^2}}}.


{{{((9-m^2/n^2)/(3-m/n))(n^2/n^2)}}}


{{{highlight((9n^2-m^2)/(3n^2-mn))}}}