Final answer:
Increasing intervals occur when y-values increase as x-values increase, while decreasing intervals occur when y-values decrease as x-values increase.
Step-by-step explanation:
Increasing intervals: as the x-values increase, the y-values increase. Decreasing intervals: as the x-values increase, the y-values decrease. When discussing the behavior of a function on an interval, increasing means the function's output (y-value) gets larger as the input (x-value) gets larger. Conversely, decreasing means the function's output gets smaller as the input gets larger.