Evaluate Expressions

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An expression is a combination of numbers, variables, and operators (like +, -, *, /) that represents a value.

To evaluate an expression means to calculate its value by substituting variables with numbers.

A variable is a symbol (often a letter) that represents an unknown value.

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

x = 4.