1. 5-6 Graphing Linear Inequalities in the Coordinate Plane
Goal:
Graph a linear inequality in the coordinate plane.
Eligible Content:
A / A

2. Vocabulary Slope Intercept Form – y = mx + b Slope – rise over run
y-intercept – point that the graph crosses the y axis

3. Solutions any ordered pairs that work in the inequality.
Any ordered pairs that are in the shaded area of the graph.
Any ordered pairs on the graph of a solid line.

4. Determining if a point is a solution
Is the point (0, 1) a solution to the inequality :
2x – 3y > -2 No
Is the point (1, -3) a solution to the inequality :
4x + 2y < 1
Yes
Is the point (-3, 6) a solution to the inequality :
x + 4y > 21

5. Graphing an inequality
Get y alone
Plot the y-intercept
Use the slope to find more points
Draw the line
If > or < line is dotted
If ≥ or ≤ line is solid
Shade one side of the line
Test the point (0,0) to see if it is a solution.

6. Where to Shade Shade above the line (UP) if you see:
y > or y ≥
Shade below the line (DOWN) if you see:
y < or y ≤

7. Graph: 2x + 3y < 6
2x + 3y < 6 -2x -2x 3y < – 2x y < – x + 2 m = - b = 2 dotted line

8. Examples y ≥ -2x + 4 -3x + 2y < 8 4x + 2y > 16 2x – 3y ≥ -6

9. Graph y – 3x < 2.
A. B.
C. D.

10. Graph x + 2y  6.
A. B.
C. D.

11. Practice
2x + y < 5
-3x + 2y ≥ 8
4x – 2y < 10
x > 4
y ≤ 3

12. Homework
Page 320 #12-22 even