Answer
a) $\left[1,5\right]$
b) $\left[-1,7\right]$.
Work Step by Step
Part a.
From the graph, the values of $x$ that satisfy the inequality $y\leq2$ are in the interval $\left[1,5\right]$.
Part b.
From the graph, the values of $x$ that satisfy the inequality $y\geq4$ are in the interval $\left[-1,7\right]$.
