Answer
$-4b$
Work Step by Step
Using the laws of exponents, the given expression, $
\dfrac{-36xb^3}{9xb^2}
,$ simplifies to
\begin{array}{l}\require{cancel}
\dfrac{\cancel{9}\cdot(-4)x^{1-1}b^{3-2}}{\cancel{9}}
\\\\=
-4x^{0}b^{1}
\\\\=
-4(1)b^1
\\\\=
-4b
.\end{array}
