#### Answer

$-39$

#### Work Step by Step

Substituting $p=-4,$ and $q=\dfrac{1}{2},$ the given expression, $
-3(2q-3p)
,$ evaluates to
\begin{array}{l}\require{cancel}
-3\left(2\cdot\dfrac{1}{2}-3(-4)\right)
\\\\=
-3\left(1+12\right)
\\\\=
-3\left(13\right)
\\\\=
-39
.\end{array}