What is a constant interval and how does it appear on a graph?

A function whose value does not vary, regardless of the input.

Pre-Calculus - Identify where a function is increasing decreasing or constant from the graph

Example: The graph shown above is decreasing from the point (3,4) to the point (5,-5), described as decreasing when 3 < x < 5. Using interval notation, it is described as decreasing on the interval (3,5). Constant: A function is constant, if as x increases (reading from left to right), y stays the same.

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