Inequality Graphing Calculator
How It Works
This inequality graphing calculator uses established formulas to provide accurate results.
The basic rule:
- Boundary line: ax + by = c
- < or >: dashed line (open boundary)
- ≤ or ≥: solid line (closed boundary)
- Test point method: pick (0,0), check if it satisfies the inequality
Results are estimates. Consult a professional for critical decisions.
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Explore Allday Everyday Math →Frequently Asked Questions
How do I graph a linear inequality?
1) Graph the boundary line (ax + by = c). Use dashed for < or >, solid for ≤ or ≥. 2) Pick a test point not on the line (usually (0,0)). 3) If the test point satisfies the inequality, shade that side; otherwise shade the other side.
When do I use a dashed vs solid line?
Use a dashed line for strict inequalities (< or >) because points on the line are NOT solutions. Use a solid line for ≤ or ≥ because points on the line ARE solutions.
What if the boundary passes through the origin?
If the line passes through (0,0), you cannot use it as a test point. Choose any other convenient point like (1,0) or (0,1) instead.