An algebraic expression is a mathematical phrase that uses:

• Numbers

• Variables (letters like x, y, a, b)

• Operation symbols ( +, −, ×, ÷, powers)

👉 The key thing to remember:
Algebraic expressions do NOT have an equals sign (=).
Once there’s an equals sign, it becomes an equation, not just an expression.

Parts of an Algebraic Expression

1. Variables

A variable is a letter that represents an unknown number.
Examples:

• x

• y

• a

👉 Example: In 3x, the x is the variable.

2. Constants

A constant is a fixed number — it does not change.
Examples:

• 4

• −7

• 12

👉 Example: In x + 5, the number 5 is a constant.

3. Coefficients

A coefficient is the number that multiplies a variable.
Examples:

• In 6y, the coefficient is 6

• In −3x, the coefficient is −3

(If there’s no number written, the coefficient is 1.)

4. Terms

A term is a part of an expression separated by + or − signs.

Example:
4x + 7 − 2y

• Terms are: 4x, 7, −2y

5. Operations

Algebraic expressions can include:

• Addition (+)

• Subtraction (−)

• Multiplication (×)

• Division (÷)

• Exponents (powers)

Examples:

• 2x + 5

• 7y² − 3

• (a + b) ÷ 2

Examples of Algebraic Expressions

What Algebraic Expressions Are Used For

• Describing real-life situations mathematically

• Solving problems in science, engineering, and economics

• Finding unknown values

• Creating equations and formulas

Example:
If a movie ticket costs $10 and you buy x tickets, the total cost is
10x