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WARM UP

A tree is 4.5 m tall and has a shadow 5.4 m long. How tall is a bush that has a shadow 1.5 m long? (Hint: Set up a proportion)

WORK WITH A PARTNER

Consider the inequality 4 > 1

Replace each with <, >, or =.

MULTIPLICATION PROPERTY OF INEQUALITY

For all real numbers a and b, for c > 0;If a > b, then ac > bc If a < b, then ac

< bc

For all real numbers a and b, for c < 0;If a > b, then ac < bc If a < b, then ac

> bc

DIVISION PROPERTY OF INEQUALITY

For all real numbers a and b, for c > 0;If a > b, then If a < b, then

For all real numbers a and b, for c < 0;If a > b, then If a < b, then

EXAMPLE

Consider the inequality -2 > -5

a)What inequality do you get when you multiply each side by 3?

b) What inequality do you get when you multiply each side by -3?

SOLVE & GRAPH

SOLVE & GRAPH

SOLVE & GRAPH

SOLVE & GRAPH

COMMUNITY SERVICE

The student council is sponsoring a recycling drive to raise money to buy food for a food bank. A case of 12 jars of spaghetti costs $13.50. What is the greatest number of cases of sauce the student council can buy if they collect $216?

HOMEWORK

Pg 188–189 # 2- 4, 11, 12, 17-22, 24