Chapter 5 - Linear Functions - 5-8 Graphing Absolute Value Functions - Practice and Problem-Solving Exercises - Page 350: 38

$x = \frac{4}{5}$

To solve for $x$, we plug in $-3$ for $f(x)$: $-3 = 5x - 7$ Add $7$ to each side of the equation to move constants to one side of the equation: $5x = 4$ To solve for $x$, divide each side of the equation by $5$: $x = \frac{4}{5}$