## Precalculus (6th Edition) Blitzer

The solution set is $(-\infty, 6)$
The idea is to isolate x on one side. Adding, subtracting or multiplying/dividing with a positive number preserves order (the inequality symbol remains). Multiplying/dividing with a negative number inverts the order (the inequality symbol changes) --- $2x+5\lt 17\qquad$ ... $/-5$ $2x\lt 12\qquad$ ... $/\div 2$, (positive) $x\lt 6$ The solution set is $(-\infty, 6)$