Lesson 6.9

Getting Started…  4x – 2y = 8  Find the x and y intercepts  Put into slope-intercept form  Graph the line.  Solve and graph: -2x -3 < 7

Graphing inequalities (>,<, ≤, ≥)  1. Get y by itself (don’t forget – if you divide by a negative, flip your sign)  2. Start at the y – intercept  3. Use your slope to plot two other points  4. Connect the dot following this rule  If > or < : dotted line  If ≤ or ≥ : solid line  5. Shade your graph following this rule: - If > or ≥ : Shade above the line - If < or ≤ : Shade below the line

Example 1:  -3y < -6x + 3  Solve for y:  Graph 3 points!  Dotted or Solid?  Shade above or below?

Next one!  3x + 2y ≤ 10  Solve for y:  Graph 3 points!  Dotted or Solid?  Shade above or below?

End of the day problem!  Graph the solution set (show your work) 5x + 2y > 4  Solve for y  Graph 3 points!  Dotted or Solid?  Shade above or below?

What is the inequality represented? x y

Word problem!  Suppose a person has less than $4.00 in nickels and dimes. Let n = the number of nickels and d = the number of dimes.  Write an inequality to describe this situation  Graph the number of possible combinations of nickels and dimes.

Homework  6.9 LM A  That’s it! Start to review for your chapter 6 test!