Chapter Nine:  Inequalities and Absolute Value

Take notes on the following topics.
Algebra 1 Notes

Chapter Nine

Section 9.1

Section 9.2

Section 9.3

Section 9.4

Section 9.5

Section 9.6

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 



Back to Mrs. Leary's Math Web Page or  Back to Algebra Contents

Section 9.2    Compound Sentences 

(Examples provided by Prentice Hall)

Part I: Conjunctions and Intersections

Determine the indicated graph.

 
Example 1   Graph the conjunction x < 7   and   x > 2.
Open circles at 2 and 7 with line joining the two circles.

Example 2 Graph 4 < x < 8.
Open circles at 4 and 8 with line joining the two circles.

Example 3 Solve and graph. 2 £ x – 5 £ 7
The inequality may be rewritten as 2 £ x – 5   and   

x – 5 £ 7. Solving separately, 7 £ x   and   x £ 12   or   

7 £ x £ 12. Closed circles at 7 and 12 with lines joining the two circles.

Part II: Disjunctions and Unions

Determine each indicated graph.

 
Example 1   Graph the disjunction x £ 0   or   x ³ 5.
Closed circle at 0 with arrow pointing left. Closed circle at 5 with arrow pointing right.

Example 2 Solve and graph 2x – 1 < 5   or   3x – 5 > 10.
Solve each inequality separately.
2x < 6   or   3x > 15
x < 3   or   x > 5
Open circle at 3 with arrow pointing left. Open circle at 5 with arrow pointing right.

 

Take class notes.

Before starting your homework, rework the examples that are illustrated in this section of your textbook and the examples that I demonstrated in class. 

Then do your homework.

Write down questions (examples or concept that you do not understand).......then.............. Ask these questions in class.