1. Solving inequalities using addition or subtraction
Tuesday October 28
Solving inequalities using addition or subtraction

2. Warm Up
Is x = 17 a solution to x > 12?
Is x = 3 a solution to 2x – 6 ≥ 0?
Is x = -3 a solution to 7 – x < 10?
Jack o’lanterns were originally made from what vegetable?

3. The jack-o'-lantern comes from an old Irish tale about a man named Stingy Jack. When Jack finally died, he was sent off to roam Earth with only a burning coal for light. He put the coal into a turnip as a lantern, and Stingy Jack became "Jack of the Lantern" or "Jack o' Lantern." Based on this myth, the Irish carved scary faces into turnips, beets and potatoes to scare away Stingy Jack or any other spirits of the night.

4. Solving Inequalities Using Addition or Subtraction
Recall that yesterday I mentioned that inequalities are like equations except inequalities have a < or > instead of a =. That is true in most cases, and I will tell you later which case it is not true. For now, though, you can treat inequalities just like you would an equation

5. Solving Inequalities Using Addition or Subtraction
Just like equations, you can add or subtract numbers from both sides of an inequality. Don’t divide or multiply just yet – we will get to that tomorrow.

6. Solving Inequalities Using Addition or Subtraction
For example, let’s look at the inequality x + 9 > 7
You can add or subtract numbers from both sides of an inequality to make it easier to find solutions.
x + 9 – 9 > 7 – 9
x > -2

7. Solving Inequalities Using Addition or Subtraction
Now lets graph
x > -2 -2

8. Solving Inequalities Using Addition or Subtraction
And x ≥ -2
You can add or subtract numbers from both sides of an inequality to make it easier to find solutions.
7 + x – 7 ≥ -2 – 7
x ≥ -9

9. Solving Inequalities Using Addition or Subtraction
Now lets graph
x ≥ -9 -9

10. Solving Inequalities Using Addition or Subtraction
Another example x - 3 > 17
You can add or subtract numbers from both sides of an inequality to make it easier to find solutions.
x >
x > 20

11. Solving Inequalities Using Addition or Subtraction
Now lets graph
x > 20 20

12. Solving Inequalities Using Addition or Subtraction
Last one x - 9 < 3
You can add or subtract numbers from both sides of an inequality to make it easier to find solutions.
x < 3 + 9
x < 12

13. Solving Inequalities Using Addition or Subtraction
Now lets graph
x < 12 12

14. Solving Inequalities Using Addition or Subtraction
Your turn. Simplify the following inequalities
x + 9 > 12
x – 12 ≤ 3
6 + x < 10

15. Classwork
Do Now: Lesson Check 3.2 Worksheet No one leaves without turning in a worksheet! When Finished: Turn in to Mr. Johnson Next: Start on homework, problems even, page