MYP 3 Mathematics · Algebra

Factorization — grouping and middle term splitting

Get started

What Is Factorization?

Before we dive into specific techniques, let's make sure we understand what factorization actually means.

Factorization

The process of writing an algebraic expression as a product of two or more factors. It is the reverse of expanding (multiplying out) brackets.

Think of factorization as the opposite of expansion:

  • Expanding:
  • Factorizing:

When we factorize, we are asking: "What was multiplied together to give me this expression?"

Analogy

Factorization is like un-baking a cake — you're figuring out the original ingredients (factors) that were combined (multiplied) to create the final product (the expression).

In this subtopic, we'll learn two powerful factorization techniques:

  1. Factorization by grouping
  2. Middle term splitting (for quadratic trinomials)

Quick Review: Taking Out a Common Factor

Before learning grouping and middle term splitting, you need to be confident with the most basic factorization skill — taking out a common factor.

Common Factor

A number, variable, or expression that divides every term of the expression exactly.

To take out a common factor:

  1. Identify the highest common factor (HCF) of all terms.
  2. Write the HCF outside brackets.
  3. Divide each term by the HCF and write the results inside the brackets.
Example

Factorize

  • The HCF of and is .
  • Divide each term: and .
  • Answer:

✅ Check by expanding: ✓

Exam Tip

Always check your factorization by expanding the brackets again — you should get back to the original expression.

Quick self-check: Try these before moving on.

  • Factorize → Answer:
  • Factorize → Answer:

If either of those felt tricky, pause and review common factors before continuing — everything that follows builds on this skill!

Free preview

13 more sections in this topic

Pick this up in your Library: it holds the whole topic, notes, cheatsheet and questions.