Glossary

Algebra – Key Terms & Definitions

Essential algebra vocabulary for IGCSE Mathematics (0580). Each term includes a clear definition and example to help you understand and remember key concepts.

variable

Core

Letter representing unknown value

Example

x in 3x + 5

coefficient

Core

Number multiplying a variable

Example

3 in 3x

constant

Core

Fixed number without a variable

Example

5 in 3x + 5

expression

Core

Combination of terms without an equals sign

Example

3x + 2y - 1

equation

Core

Statement with equals sign

Example

3x + 5 = 14

formula

Core

Equation showing relationship between variables

Example

$A = \pi r^2$

term

Core

Single number, variable, or product

Example

3x is one term

like terms

Core

Terms with same variable and power

Example

3x and 5x are like terms

factorise

Core

Write as a product of factors

Example

$x^2 + 5x + 6 = (x+2)(x+3)$

expand

Core

Multiply out brackets

Example

2(x+3) = 2x + 6

simplify

Core

Write in simplest form

Example

3x + 2x = 5x

substitute

Core

Replace variable with a value

Example

If x=3, then 2x+1=7

quadratic

Core

$\text{Expression with } x^2 \text{ as highest power}$

Example

$x^2 + 3x - 4$

linear

Core

Expression with x as highest power

Example

2x + 3

simultaneous equations

Extended

Two or more equations solved together

Example

x + y = 7 and x - y = 3

index

Core

Power or exponent

Example

$\text{In } x^3 \text{, 3 is the index}$

subject

Core

Variable on its own on one side

Example

In y = mx + c, y is the subject

algebraic fraction

Extended

Fraction with variables

Example

$\dfrac{x+1}{x-2}$

Need help understanding these concepts?

Teacher Rig explains them through worked examples.

Book a Free Trial

Frequently Asked Questions

How many algebra terms do I need to know for IGCSE?

This glossary covers 18 key algebra terms. Focus on understanding definitions and being able to use each term in context during exams.

Are these terms for Core or Extended?

Terms are labelled as Core or Extended. Core students should focus on Core-labelled terms, while Extended students need to know all terms.

Need Help with IGCSE Maths Concepts?

Book a free trial class with Teacher Rig for personalised concept explanations.

Book Free Trial WhatsApp Us