Graphing One-Variable Inequality


Press CLEAR to clear the home screen. Enter the inequality. Press MATH, NUM, 1:abs( to get absolute value. Press 2 ND MATH (TEST) to find the ≥ sign.



 Press ZOOM 6 to get the standard window. If the inequality is true the graph Y = 1 will show. Where the inequality is false, the graph will not show. 


Use 2ND TRACE and 1:value to see if the end point of the segment or ray is part of the solution. We have X = - 5 and Y = 1 means that X = -5 is part of the solution.


Similarly, we find X = -1 and Y = 1. So, X = -1 is part of the solution. The solution is X ≤ -5 or X ≥ -1. In interval notation, we have the solution (-∞, -5] U [-1, ∞).




If the inequality were changed to >, then X = -5 yields Y = 0 which means X = -5 is NOT part of the solution because the inequality is false (Y=0).