A numeric expression is a mathematical phrase that includes numbers and operations but no variables. Example: 100 - 12² + 5.

An algebraic expression is a mathematical phrase that includes numbers, variables, and operations. Example: 2x + 3.

A coefficient is a numerical factor in a term of an algebraic expression. Example: In 3x, 3 is the coefficient.

A variable is a symbol (often a letter) that represents an unknown value in an expression or equation. Example: In 2x + 3, x is the variable.

A term is a single mathematical expression that can be a number, a variable, or a combination of both. Example: In 4x + 2 - 7, there are three terms: 4x, 2, and -7.

A power is an expression that represents repeated multiplication of a number by itself. Example: In 2², 2 is the base and 2 is the power.

An equation states that two expressions are equal and includes an equals sign (=). An expression does not include an equals sign.