Lines and Slope: Graphing Linear Inequalities

-  To graph a linear inequality, first draw a graph of the "equals" line.
-  Use a dash line for less than () and greater than () signs and a solid line for less than and equal to () and greater than and equal to ().
-  Choose a testing point. (it can be any point on both sides of the line.)
-  Put the value of of that point in the inequality. If that works, that part of the line is the solution.

If the values don’t work, then the other part of the line is the solution.

Example:
Sketch the graph of inequality:
Solution: To draw the graph of , you first need to graph the line:

Since there is a less than () sign, draw a dash line.

The slope is and -intercept is . 
Then, choose a testing point and substitute the value of and from that point into the inequality.

The easiest point to test is the origin:

This is correct! is less than . So, this part of the line (on the right side) is the solution of this inequality.