1. 5-1 Solving Linear Inequalities by addition and Subtraction
Goals:
Graph linear inequalities on a number line.
Solve linear inequalities by adding and subtracting.
Using linear inequalities to solve real life problems.
Eligible Content:
A / A

2. Vocabulary Inequality – any problem containing <, >, ≤ or ≥.
Graph – all numbers on a number line that will work in the inequality.
Solve – get the variable alone.

3. Graphing a Linear inequality
Graph: x < 2 x ≤ -2 x > - 4 x ≥ 3

4. Summary < and >  draw an open circle:
≤ and ≥  draw a closed circle:
Shade in the direction the inequality symbol points.
< and ≤  shade left
> and ≥  shade right

5. Examples
Graph each inequality:
x < 6
x ≥ -4
4 < x
x ≤ -2

6. Solve the inequality (same as before)
x + 7 < x < 5 x - 2 ≥ x ≥ 17

7. Examples Solve each linear inequality: x + 3 < 4 x – 9 ≥ 4
x < 1 x ≥ 13 x > 3 x < -18 x > 6

8. Solve k – 4 < 10.
A. k > 14
B. k < 14
C. k < 6
D. k > 6

9. Solve the inequality m – 4  –8.
A. m  4
B. m  –12
C. m  –4
D. m  –8

10. Solve 3p – 6 ≥ 4p. Graph the solution.
B. p ≤ –6
C. p ≥ –6
D. p ≥ –6

11. Practice
Page 288 #1-8

12. Word Problem #1
Megan wants to buy season passes to two theme parks. If one season pass costs $54.99 and Megan has $100 to spend on both passes, the second season pass must cost no more than what amount?
x ≤ 100
x ≤ 45.01
Less than $45.01

13. Word Problem #2
Jeremy is taking two of his friends out for pancakes. If he spends $17.55 on their meals and has $26 to spend in total, Jeremy’s pancakes must cost no more than what amount?
x ≤ 26
x ≤ 8.45
Less than $8.45

14. Word Problem #3
The temperature for a lizard cage has to be at least 82°F. Currently the temperature is 62.5°F. How much warmer does the cage need to be? x ≥ 82 x ≥ 19.5 At least 19.5°F warmer

15. Homework
Pages #12-28 even
#34-39 all