COMPOUND INEQUALITIESAKA: Compound Inequalities

Lesson 4-8

Math Vocabulary Review

Inequality:

A math sentence or statement

that compares (<, >, <, >)

a point/points on a number line

5 > m

Compound Inequality:

Two inequalities that are joined by the word and or the word or.

and: 32 < t < 40 or: 32 < t or t > 40

Example 1

“AND”

-4 < r – 5 < -1

+5 + 5 +5

1 < r < 4

*the process to solve one side [of a normal inequality], is used to solve ALL parts of a compound inequality

Graph: -----------------------------------

Example 2

“AND”

r + 8 > -1 and 3r < 3

-8 -8 3 3

r > -9 and r < 1

Graph: -----------------------------------

Example 3

“OR”

4v + 3 < -5 OR -2v + 7 < 1

- 3 -3 -7 -7

4v < -8 OR -2v < -6

4 4 -2 -2

v < -2 OR v > 3*two separate inequalities to solve & graph

Graph: -----------------------------------

Example 4

“OR”

v – 3 < -4 OR v – 3 > 4

+ 3 +3 + 3 +3

v < -1 OR v > 7*two separate inequalities to solve & graph

Graph: -----------------------------------

Practice

Solve & Graph

a) -3 < z – 1 < 6----------------------------

b) 0 < -8b and -4b < 12 ---------------------------

c) 7t > 49 or 2t < -4 ---------------------------

Homework

p. 198 #3-6, 13-24 (skip 16, 18, 19)