Final answer:
A symbol that stands for a quantity that can change or have any one of a set of values is called a variable. Variables are commonly used in algebra and are an essential concept in solving equations and representing unknowns in mathematical problems.
Step-by-step explanation:
Mathematics
A symbol that stands for a quantity that can change or have any one of a set of values is called a variable.
For example, in the expression 2x + 3, x is a variable. It can be replaced with any number, and the value of the expression will change accordingly.
Variables are commonly used in algebra and are an essential concept in solving equations and representing unknowns in mathematical problems.
Learn more about Variables in mathematics