In this section, you will review the definitions of independent and dependent variables and functional relationships.

In Algebra, variables may be independent or dependent.

An independent variable does not depend on the value of another variable.

The dependent variable depends on the value of another variable.

In the equation y = 2x – 3, if someone gives you a value for x, you can determine the corresponding value for y. In this equation, x is referred to as the independent value, and y is the dependent value. The value of y depends on the value of x.

In the equation y = 2x – 3, both x and y are variables, and there is a special relationship between the two variables. It is called a functional relationship. A functional relationship exists when you get only one answer for y when you substitute a value for x.