One thing I learned this week in Pre Calc 11 is how to graph linear equations in two variables. A linear equation divides a graph into two sections. A linear equation has variables to the first degree only, and the variables are never squared, cubed, or taken to any other power. A linear inequality looks very similar to a linear equation, the difference between the two is that a linear equation has a “equals” symbol and a linear inequality has a “inequality” symbol. When writing or understanding a graph of a linear inequality we shade one side of two sections divided by the linear equation. The side of the linear equation that is shaded is the region that will “satisfy” the inequality.

To find the region that will satisfy the inequality we choose a point (called the test point) on either side of the slope and plug it into the linear inequality. Then solve the linear inequality. If the inequality sign is true to the numbers then shade in the region, if not shade in the opposite region on the graph.

Below is a example of how I graphed a linear equation in two variables using the steps above…