Chapter 2 - Equations, Inequalities, and Problem Solving - 2.1 Solving Equations - 2.1 Exercise Set - Page 87: 81

$x=-15$

Using properties of equality, the solution to the given equation, $ -24=\dfrac{8x}{5} $, is \begin{array}{l}\require{cancel} \dfrac{5}{8}\cdot(-24)=\dfrac{8x}{5}\cdot\dfrac{5}{8} \\\\ \dfrac{5}{\cancel{8}}\cdot(\cancel{8}\cdot(-3))=\dfrac{40x}{40} \\\\ -15=x \\\\ x=-15 .\end{array}