## Elementary and Intermediate Algebra: Concepts & Applications (6th Edition)

$\text{Set Builder Notation: } \left\{ y|y\le-13 \right\} \\\text{Interval Notation: } \left( -\infty,-13 \right]$
$\bf{\text{Solution Outline:}}$ Use the properties of inequality to solve the given inequality, $-5y\ge65 .$ Write the answer in both set-builder notation and interval notation. $\bf{\text{Solution Details:}}$ Dividing both sides by a negative number (and consequently reversing the inequality symbol), the inequality above is equivalent to \begin{array}{l}\require{cancel} -5y\ge65 \\\\ y\le\dfrac{65}{-5} \\\\ y\le-13 .\end{array} Hence, the solution set is \begin{array}{l}\require{cancel} \text{Set Builder Notation: } \left\{ y|y\le-13 \right\} \\\text{Interval Notation: } \left( -\infty,-13 \right] .\end{array}