Independent/Dependent Variables

Function Machine

Input

Output

IN

Out

x

Y or f(x)

Independent Variable

Dependent Variable

Domain

Range

Dependent and Independent Variables

In a function, the value of the y-coordinate depends on the value of the x-coordinate.

Therefore, Y is the dependent variable and X is the independent variable.

Independent and Dependent Variables

Circle the Dependent Variable in each pair below:

1. Hours worked Paycheck amount

2. Six-week grade Test score

3. Profit Units sold

4. Attendance Employability Skills Grade

The paycheck amount depends on the number of

hours worked so the paycheck amount is the

dependent variable

The six-week grade depends on the test score so the six-week grade is the dependent variable

Indep/Dep VariablesIn an equation the variable by itself is the

dependent variable.

Example: y = x +3

y depends on x

Dependent variable: yIndependent variable: x

1. r = 17s + 23

Dependent variable ____________ Independent Variable ____________

2. The formula gives the area of a circle with a radius r.

Dependent variable________________

Independent Variable_______________

2rA

r

s

A, Area

r, radius

Name the dependent and independent variables.

On a graph the variable on the y-axis is the dependent variable

The variable on the x-axis is the independent variable

Indep/Dep Variables

# of touchdowns

Score

Dependent Variable

Independent Variable

# records soldprofit

1.

2.

# absences

grade

Dependent Quantity

_________________

Independent Quantity

__________________

Dependent Quantity

_________________

Independent Quantity

__________________

profit

# records sold

grade

# absences

Name the dependent and independent variables.

Table• In a table normally the independent

variable is on the left and the dependent variable is on the right

x y

1 2

5 12

6 15

9 24

12 56

Independent Variable

Dependent Variable

Table Examples• Name the independent variable and

dependent variable

D T

0.2 20

0.3 30

1.2 120

1.4 140

1.7 170

Independent:

Weebles Woobles

-2 15

-1 20

0 25

1 30

2 35

Dependent:D

TIndependent:Dependent:

WeeblesWoobles