Increasing from 6 a.m. to noon and from 2 a.m. to 6 a.m. Decreasing from noon to 2 a.m.
Work Step by Step
Using the graph we notice the intervals on which the function is increasing/decreasing: -The temperature was increasing from $x=0$ to $x=6$ (from 6 a.m. to noon). - The temperature was decreasing from $x=6$ to $x=20$ (from noon to 2 a.m.). - The temperature was increasing from $x=20$ to $x=24$ (from 2 a.m. to 6 a.m.).