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DEPENDENT VARIABLE

Dependent Variable

Definition Of Dependent Variable

Dependent Variable is a variable whose value depends on the values of one or more independent variables.

Example of Denominator

In p = 4q, p is the dependent variable, because its value depends on the value of q.
In z = 3x2 - 2y3, z is the dependent variable.

Video Examples: The Kid-Friendly Definition of Dependent Variables : Algebra
 

Solved Example on Dependent Variable

Ques: What is the dependent variable in the function f(x) = 3 - x?

Choices:

A. no dependent variable
B. 3 
C. f(x)
D. x
Correct Answer: C

Solution:

Step 1: In the function f(x) = 3 - x, the value of f(x) depends on the value of x. So, f(x) is the dependent variable.

Quick Summary

  • The dependent variable's value is determined by the independent variable.
  • In an equation, it is the 'output' or result of the function.
\[ y = f(x) (where y is the dependent variable) \]

⚠️ Common Mistakes

  • Confusing the dependent variable with the independent variable.
  • Assuming a variable is independent without considering the context of the equation.

🌍 Real-World Uses

  • In a scientific experiment, the amount of plant growth (dependent variable) depends on the amount of fertilizer used (independent variable).
  • The cost of a taxi ride (dependent variable) depends on the distance traveled (independent variable).
  • A student's exam score (dependent variable) depends on the amount of time they spent studying (independent variable).

📋 Standards Alignment

  • CCSS.MATH.CONTENT.HSA.REI.A.1
  • CCSS.MATH.CONTENT.HSA.REI.C.6

🔗 Related Links

🍎 Teacher Insights

Use real-world examples to illustrate the concept, such as the amount of plant growth (dependent) depending on the amount of water (independent).

🎓 Prerequisites

  • Variables
  • Independent Variables
  • Functions

Check Your Knowledge

Q1: In the function g(t) = 5t + 2, which is the dependent variable?

Q2: Which of the following best describes a dependent variable?

Frequently Asked Questions

Q: How do I identify the dependent variable in an equation?
A: Look for the variable that is being 'solved for' or is expressed in terms of other variables. It is the output of the function.

Q: Can a variable be both dependent and independent?
A: Yes, in more complex models or systems, a variable can be dependent in one equation and independent in another. It depends on the relationship being modeled.

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