Concept

# Algebraic Expression

If a calculation contains at least one variable, it is called an algebraic expression. For example, $2x + 3$ is an algebraic expression because it contains the variable $x.$

Numbers written in front of the variables are called coefficients, specifying how many of the variable there are. The terms not containing any variables are called constants. Because $x$ can be any value, substituting values for $x$ into the algebraic expression can result in infinitely many values.

Sample $x$-value Expression Simplified expression
${\color{#0000FF}{5}}$ $2({\color{#0000FF}{5}})+3$ $13$
${\color{#0000FF}{\text{-} 1}}$ $2({\color{#0000FF}{\text{-} 1}})+3$ $1$

Note that an expression that only contains constants is called a numeric or numerical expression.