Solving Inequalities with Multiplication and Division

Here is the Big Rule

• Big Rule- If you multiply or divide by a negative, you must switch the inequality

• Everything else is the same

4x > 32

Ex 1

65

x

315

z

Ex 2

5 20t

6x + 3 > 33

-3x – 5 < 23

Real World

• An elevator can carry up to 2,500 lb. Suppose the weight of an average adult is 150 lb. At most how many average-sized adults can safely ride the elevator at the same time?

With a partner

• Jessica is saving up to buy a new car. She needs to save at least 6 times more than she has already saved. How has she already saved if the car costs $24,000?

Closure

• What is our very important rule??????