1. 3.3 Solving Inequalities Using ×/÷
Objective: SWBAT solve inequalities using multiplication and division.

2. Mini Quiz 21 1. Solve and graph 6 + b – 7 < 5 2. Solve and graph
3. Is -5 a solution to the inequality n > -17

3. Overview Solving inequalities using multiplication and/or division
Solving and checking solutions

4. Quick Review 1. Solve and graph k ≥ 6
2. For inequalities, what are the two types of checks you need to do?
check computation and check inequality

5. Question: When do you switch the signs?
Multiply 3 to each side:
< 9
-15 __ 27
2. 3 > 1
9 __ 3
Divide 3 to each side:
< 33
-5 __ 11
> -21
-3 __ -7
Multiply -3 to each side:
5. 5 < 9
-15 __ -27
> -3
3 __ 9
Divide -3 to each side:
< 33
5 __ -11
> -9
-9 __ 3
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Answer: When you х or ÷ by a negative number!!!

6. Multiplication and Division of Inequalities
Solve and graph each inequalities
9. -5x ≥ 25
x ≤ -5
Checking your solution:
Check Computation
-5x = 25
-5(-5) = 25
25 = 25
2. Check Inequality
-5x ≥ 25
-5(-6) ≥ 25
30 ≥ 25 -5

7. Multiplication and Division of Inequalities
Solve and graph each inequalities ( solutions)
9. -5x ≥ 25
t < -8
11.
12.
x ≤ -5
t > 4
n > 2
y < -2

8. Application
13. The student council votes to buy food for a local food band. A case of 12 jars of spaghetti sauce costs $ What is the greatest number of cases of sauce the student council can buy if they use at most $216 for this project?
13.75c ≤ 216
c ≤
The most they can buy is 15 cases.

9. Wrap Up Solve inequalities by Check solutions
×/÷
Check solutions
 computation
 inequality
HW: P #1-41 EOO; odd
Write DLUQ: When do you need to switch the signs?