Chapter 4 - Section 4.3 - Equations and Inequalities Involving Absolute Value - Exercise Set - Page 283: 19

{$-\dfrac{2}{5},\dfrac{2}{5}$}

Given: $7|5x|+2=16$ This can also be written as: $7|5x|=14$ or, $|5x|=2$ As per definition of absolute value, we have $5x=2$ and $5x=-2$ Thus, $x=\dfrac{2}{5}$ and $x=\dfrac{-2}{5}$ Hence, {$-\dfrac{2}{5},\dfrac{2}{5}$}