1. Direct Variation 2.4

2. Big idea… 5280ft=1mile. There will always be the same number of feet in a mile, so they are “directly proportional”

3. Definitions Direct Variation: When two things are related by a constant ratio Equation: The numbers x and y and directly proportional, and k is called the constant of variation.

4. Why is it called DIRECT? If x or y increases, so does the other. If x or y decreases, so does the other. They move together in unison.

5. Example 1

6. Example 2

7. Example 3: You try!

8. Example 4

9. Example 5 Your job pays you $9.50 an hour. 1.Define variables (x and y) 2.Write a direct variation equation. 3.How much will you make if you work 8 hours? 4.How many hours did you work if you make $114?

10. You try! You drive at a constant speed of 35 mph. 1.Define variables (x and y) 2. Write a direct variation equation. 3. How far will you go if you drive for 4 hours? 4. If you travel 175 miles, how long did you drive?

11. Homework 2.4: problems 3,4,5.