Independent vs Dependent Algebra Word Problems

Independent and Dependent

Which is Which???

Independent Variables

• The input

• The number you start with

Dependent Variables

• The output

• The result of a change to the Independent variable

Example

3x + 2 = y, where x = 4

The x is the Independent. You are given the number for x.

The x is part of the input. The x is multiplied with the 3 and then 2 is added to the product.

The y is the Dependent. You were not given the number for y.

The y is part of the output. Nothing is done to the y.

Think of dependent as "it depends on what the independent does."

Multiple Choice

Identify the dependent variable for 5p - 7 = t

• 5p

• 7

• t

Multiple Choice

Identify the independent variable in this equation.

9(4+w) = b

• 9

• (4+w)

• w

• b

Multiple Choice

Identify the dependent variable in this situation.

Charlie has a summer job mowing lawns. The amount of money he earns is determined by how many lawns he mows.

• amount of money earned

• number of lawns mowed

Multiple Choice

Identify the independent variable in the following situation.

Mateo is taking a test. The more questions he gets correct, the higher his test score will be.

• test score

• correct questions