Presentation on theme: "Graphing Linear Inequalities in Two Variables"— Presentation transcript:
1Graphing Linear Inequalities in Two Variables Objective: Graph all of the solutions to a linear inequalityNCSCOS: 1.02, 3.03, 4.01
2Steps to RememberRewrite the inequality so that it is in slope-intercept formy = mx + bPlot the y-intercept (b)Use the slope (m) to find other points on the line.Draw the lineSolid if <= or >=Dotted if < or >Shade above or below the lineAbove if > or >=Below if < or <=
3Example 1Graph y > 2x -5The equation is already in slope-intercept form.Start by plotting the y-intercept (b = -5)
4Example 1 (cont) Graph y > 2x -5 Now use the slope to find other points on the line
5Example 1 (cont) Graph y > 2x -5 Draw a dotted or solid line through the coordinates.This line will be dotted since the inequality is >
6Example 1 (cont) Graph y > 2x -5 Shade above the line to show all of the coordinates that are solutions.
7Example 2 Graph 2x - 5y >=15 First, solve for y … -5y >= -2x + 15y <= 2/5 x – 3Now go through the steps of graphing.
8Example 2Graph 2x - 5y >=15y <= 2/5 x – 3Plot the y-intercept
9Example 2 Graph 2x - 5y >15 y <= 2/5 x – 3 Use the slope to find other points
10Example 2 Graph 2x - 5y >15 y <= 2/5 x – 3 Draw a solid line through the points.
11Example 2Graph 2x - 5y >15y <= 2/5 x – 3Shade below the line
12Special Example Graph x > 5 Remember the graph will be a vertical line.
13Special Example Graph y< -2 Remember the graph will be a horizontal line.