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Visualizing Quadratic Inequalities on a Number Line

Your Task

In this task, you will explore how to represent quadratic inequalities on a number line. Start by working with a given quadratic inequality in the form (or using symbols such as , or <)
Explore different values for a, b, and c in the quadratic inequality , answer the following questions to help you represent the solutions clearly on a number line:

Identifying the Critical Points

At which x-values does the graph touch or cross the x-axis? How can you mark these points on the number line?

Identifying the Critical Points

How do these points divide the number line into different regions (or intervals)?

Determining the Solution Set on the Number Line

How can you determine which regions of the number line should be shaded based on where the graph is above or below the x-axis?

Determining the Solution Set on the Number Line

When should you use open circles (for > or  <) or closed circles (for ≥ or ≤ ) at these points on the number line?

Expressing the Solution

How can you express the shaded regions on the number line using inequality notation, interval notation, or set notation?

Expressing the Solution

How would the number line change if the quadratic inequality has exactly one solution (the graph just touches the x-axis at a single point)?

How do these points divide the number line into different regions (or intervals)?