Answer
$(-\infty,\dfrac{-1}{3}]\cup [3, \infty)$
Work Step by Step
Given: $|4-3x| \geq 5$
or, $4-3x \geq 5$
or,$-3x \geq 1$
or, $x \leq \dfrac{-1}{3}$
Now, $|4-3x| \geq 5$
or, $4-3x \leq -5$
or,$x \leq -5-43$
or, $x \geq 3$
Hence, $(-\infty,\dfrac{-1}{3}]\cup [3, \infty)$