Dependent Variable
High School
Definition
Dependent variable is a variable that its value is to be determined by the value(s) of independent variable(s). For example, in y = 2x + 7, y is the dependent variable and its values depend on the values of x.
Worked examples
\(y = 2x + 7\)
\(y\) is the dependent variable because its value depends on whatever \(x\) is.
\(A = \pi r^2\)
Area \(A\) is the dependent variable; it depends on the radius \(r\).
Common mistakes
- In \(y = 3x - 5\), \(x\) is the dependent variable → \(y\) is the dependent variable The dependent variable is the output — what you solve for or what changes in response to the independent variable.
- The dependent variable is always \(y\) → Any variable can be dependent if its value depends on another In \(x = 4t + 1\), \(x\) is dependent on \(t\). The label matters less than the relationship.
- Dependent and independent variables are the same thing → Dependent variables respond to independent variables Independent variables are chosen or controlled; dependent variables are the result or output.
Where you'll use it next
You'll use dependent variables when graphing functions, interpreting real-world relationships in word problems, analyzing data in statistics, and setting up experiments in science courses.
Found in 1 StudyPug lesson
Relationship Between Two Variables
10th Grade10thAlgebra 1
A relationship between two variables shows how the dependent variable changes as the independent variable changes.
See also
Reviewed by Pat Cheng, M.Ed. — StudyPug Curriculum Lead · Last updated June 6, 2026