1. Direct Variation Equation for direct variation:

2. Page 6 Steps: 1.Set up a proportion 2.Cross multiply and solve for variable Since x varies directly as y, we write x in numerator, y in denominator. Not a bad idea to write a generic ratio.

3. Page 6

5. Page 7

7. Check to make sure that the constant of variation is the same all the way across! Since the constant is the same, it is direct variation!

8. Page 7 Check to make sure that the constant of variation is the same all the way across! Since the constant is not the same, it is not a direct variation!

9. Page 8

10. Since the population is growing at a constant rate, I can just multiply the number of years from 2007 by 250. There will be 750 additional people in 2010!

11. Homework – YAY!!!!! Page 6 #4,6,7,8 Pages 7-8 #1,3,6,11,12,15