1. Variables are values that change
Variables are values that change. In algebra we represent variables letters such as x, y, z. Those letters represent data from the real world.
Temperature (x) 50 60 70 80 90
100
# of fans sold
(y) 1 2 5 15 25

2. Variables can be classified as either independent or dependent.

3. Dependent Variable
The dependent variable DEPENDS on the independent variable. Example: Cost of restaurant bill Number of meals you ate Your bill at a restaurant depends on the number of meals you ate.

4. The dependent variable is always located on the y-axis of a graph.
# NUMBER OF MEALS 1 2 3
$ Cost of meal
$10
$20
$30
The dependent variable is always located on the y-axis of a graph.

5. Independent Variable
The independent variable is the variable that comes first.
Example: temperature
# of fans sold
The temperature determines how many fans will be sold.

6. The independent variable is always located on the x-axis of a graph.
temperature 50 70
100
# of fans sold 1 5
The independent variable is always located on the x-axis of a graph.

7. D R
I D
X Y

8. A student’s grade & amount of time spent studying.
_________________ depends on
__________________
Independent variable:__________
Dependent variable:___________

9. Time spent exercising & number of calories burned.
_________________ depends on
__________________
Independent variable:_________
Dependent variable:___________

10. 3. The amount of money you make and the number of hours you work.
Independent variable: _____________
Dependent variable:_____________
4. The number of sodas you buy and the total money spent.
Independent variable:______________
Dependent variable:_______________
5. The number of houses you can paint depends on how much time you have.
Hours worked
Amount of money
Number of sodas
Total money
Amount of time
Number of houses