Answer
$\dfrac{6m-4}{3m-4}$
Work Step by Step
The given expression, $
\dfrac{m-4}{3m-4}-\dfrac{5m}{4-3m}
,$ simplifies to
\begin{array}{l}\require{cancel}
\dfrac{m-4}{3m-4}-\dfrac{5m}{-(-4+3m)}
\\\\=
\dfrac{m-4}{3m-4}-\dfrac{5m}{-(3m-4)}
\\\\=
\dfrac{m-4}{3m-4}+\dfrac{5m}{3m-4}
.\end{array}
Since the fractions are similar, then copy the common denominator and add/subtract the numerators. Hence, the expression, $
\dfrac{m-4}{3m-4}+\dfrac{5m}{3m-4}
,$ simplifies to
\begin{array}{l}\require{cancel}
\dfrac{m-4+5m}{3m-4}
\\\\=
\dfrac{6m-4}{3m-4}
.\end{array}