1. Proportions
Chapter 5
Section 5.3

2. Objective
The students will learn whether ratios form a proportion by using equivalent ratios and cross products.

3. Vocabulary Proportion – and equation stating two ratios are equal
Cross products – are the two products found by multiplying the numerator of one ratio by the denominator of the other

4. Key Concept
Ratios that are equal form a proportion.(Written in simplest form.)
Arithmetic Algebra
6 8 = 𝑎 𝑏 = 𝑐 𝑑 , b≠0 𝑎𝑛𝑑 𝑑≠0

5. Example
Are and propprtional

6. Example
Are and proportional

7. Example
Are and proportional

8. Key Concept
If two ratios form a proportion, the cross products are equal. If two ratios have eq
Arithmetic Algebra
6 8 = 𝑎 𝑏 = 𝑐 𝑑 ,
6∙12=8∙ ad = bc , b≠0 𝑎𝑛𝑑 𝑑≠0

9. Example
5 9 , 30 54

10. Example
7 8 , 55 65

11. Exit Ticket
Is 𝑎𝑛𝑑 proportional?

12. Exit Ticket
𝐷𝑜 𝑡ℎ𝑒 𝑟𝑎𝑡𝑖𝑜𝑠 6 9 𝑎𝑛𝑑 4 6 𝑓𝑜𝑟𝑚 𝑎 𝑝𝑟𝑜𝑝𝑟𝑡𝑖𝑜𝑛?

13. Questions?

14. Worksheet