A2AlgebraFoundation
Expanding Brackets
Expanding (or “multiplying out”) brackets means getting rid of the brackets by multiplying everything inside by what is outside. It is the reverse of factorising.
What you'll learn
- Expand a single bracket
- Expand and simplify
- Expand double brackets (FOIL)
- Avoid sign mistakes
1
Single brackets
Multiply the term outside by each term inside: . Watch the signs carefully when the outside term is negative.
1.
2.
Answer
2
Double brackets
Each term in the first bracket multiplies each term in the second — a method often called FOIL (First, Outer, Inner, Last). Then collect like terms.
Expanding two brackets.
1; outer ; inner ; last .
2Collect: .
Answer
Tip — A negative times a negative is positive — a common place to slip up.
Remember these
Single bracket.
Double brackets.
Watch out for these
Only multiplying the first term: .
Multiply everything inside: .
Getting the sign wrong: .
, so .
Key takeaways
- Multiply the outside term by every term inside.
- Double brackets: multiply each pair (FOIL), then collect like terms.
- Take care with negative signs.
Test yourself
Ready to practise Expanding Brackets? Pick a mode and earn XP & Dobloons.