Evaluating expressions

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Evaluating expressions involves substituting values for variables in an expression and performing the necessary arithmetic operations.

A variable is a symbol (often a letter) that represents an unknown value in an expression or equation.

Simplifying an expression means to reduce it to its simplest form by combining like terms and performing arithmetic operations.

The order of operations is a set of rules that dictates the sequence in which calculations are performed: Parentheses, Exponents, Multiplication and Division (from left to right), Addition and Subtraction (from left to right) - often abbreviated as PEMDAS.

A polynomial is a mathematical expression that consists of variables, coefficients, and non-negative integer exponents, combined using addition, subtraction, and multiplication.