GRAPHING GUIDE
Start with the graph
Replace the inequality sign with an equals sign to get the boundary. Use a solid line for ≤ or ≥ and a dashed line for < or >.
Worked example
For y > 2x − 1, draw the boundary y = 2x − 1 as a dashed line. Test (0, 0): zero is greater than −1, so shade the side containing the origin.
Try another example
For y ≤ −x + 2, draw a solid boundary. The point (0, 0) satisfies the inequality, so shade its side and include the line.
Check your result
Use the calculator to plot the boundary equation. Mark the shading separately if your tool only accepts functions. Pick a test point off the line.
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