Algebra 1 19 April 2011SILENTLYSILENTLY

Homework due next class: pg. 318: 8, 14

Warm up:Solve each inequality for y:1) 84x + 7y > 70

2) 4.8x – 0.12y < 7.2

ObjectiveStudents will be able to graph and solve two variable

inequalities.

Homework Due TODAYpg. 316: 3, 5

Include basic information Show all steps Use graph paper

√ or X for full points-10 if you don’t check your work

Graphing two variable inequalities

Look at pg. 315, example BBASICS:1. Rewrite the equation in y-intercept form2. Draw the boundary line: - - - - - - - for < or > (like “open” dot) for < or > (like “closed” dot)3. Pick a test point and check it in the equation SHADE the half plane that contains the solution

points

Linear graphing basics

Slope-intercept form y = mx + b m = slope =

b is the y-intercept or the y value when x = 0

2 1

2 1

y yrise y

run x x x

TEST NumbersGraphing Linear Inequalities handout#7. y < -2x + 2 DOTTED or SOLID line?Graph y = -2x + 2 using y-intercept and slope or using a tableCheck the following points to see if they make the

inequality true by substituting:1. (-1, -1) 2. (-2, -2) 3. (1,1) 4. (2, 2)5. (-3, -3) 6. (3, 3) 7. (0, 0)

Shade the region above or below the line that makes the inequality true

Graphing Inequalities in two variables

Finish notes handout together- KEEP IN YOUR NOTEBOOK FOR REFERENCE

DO GRAPHING LINEAR INEQUALITIES HandoutPLACE in group folder at end of class

Practice

pg. 315: Do #7: Find the equation: y = b + mx slopewhere increasing by how much?does orit start? decreasing?

more practice…10. a - d THINK- SILENTLYread question and write basic information on your paper-a. DEFINE your variables/ write your inequalityb. Boundary equation/ write = in place of <PAIR- check with your partner- do you agree?SHARE- whole class checkc and d- GRAPH your inequality Find three points