Learning Objectives
- Explain what expanding brackets means.
- Identify how many terms are inside a bracket.
- Expand simple algebraic expressions correctly.
- Avoid common mistakes when expanding brackets.
Introduction
This lesson develops Expanding Brackets from meaning and patterns before moving to calculations. Look for what the quantities, shapes or symbols represent, then connect that idea to the method.
Key Notes
Read the definitions and key facts below carefully. Each rule is most useful when you can explain why it fits the situation, not simply recall it.
๐ฌ Distribute to every term
The term outside multiplies every term inside.
๐ค Think About This...
A teacher is preparing prize packs for learners. Each prize pack contains:
- ๐ 2 exercise books
- โ๏ธ 1 pencil
There are 5 learners. Instead of writing the same thing five times, we can write:
Now multiply everything correctly.
This is exactly what we do when expanding brackets in Algebra.
๐ What Does "Expand" Mean?
To expand brackets means multiplying the number or expression outside the bracket by the correct term or terms inside the bracket.
๐ง The StudyNest Thinking Method
๐ How many terms are inside the brackets?
A term is a part of an expression separated by a plus (+) or minus (โ) sign.
There are 2 terms.
- x
- 2
There is only 1 term because there is no plus or minus sign.
๐ Worked Examples
Example 1
Expand:
๐ StudyNest Question: How many terms are inside the brackets?
There are 2 terms.
- x
- 2
Multiply each term once.
Example 2
Expand:
๐ StudyNest Question: How many terms are inside the brackets?
Only one term.
Multiply the whole term.
5 ร 2 = 10
5 ร x = 5x โ
Example 3
Expand:
๐ StudyNest Question: How many terms are inside the brackets?
There are 2 terms.
- 3x
- 5
Multiply each term once.
Example 4
Expand:
Multiply the 7 by both terms.
โญ Expanding Two Brackets: The FOIL Method
So far, we have expanded expressions with one bracket.
We can also multiply two brackets, such as:
Each term in the first bracket must multiply each term in the second bracket.
F โ First
O โ Outside
I โ Inside
L โ Last
Example: Expand (x + 2)(x + 5)
x ร x = xยฒ
x ร 5 = 5x
2 ร x = 2x
2 ร 5 = 10
Now write all four products:
Collect the like terms:
FOIL is only a memory shortcut for multiplying two brackets containing two terms each.
The real rule is still: multiply every term in one bracket by every term in the other bracket.
๐ Real-Life Example
A school is preparing prize packs. Each pack contains:
- 3 pens
- 2 pencils
There are 8 prize packs.
Multiply each item by 8.
Expanding brackets simply means multiplying every term in the bracket correctly.
โ Common Mistakes
Forgetting to multiply the second term.
3(x + 5) โ 3x + 5 โ
Treating 2x as two separate terms.
Remember: 2x is ONE term.
Forgetting that multiplying a negative number gives a negative answer.
Practice Questions
Expand the following expressions.
- 2(x + 7)
- 4(a + 3)
- 6(y โ 2)
- 3(2m + 5)
- 9(p โ 4)
- 5(4x)
- 8(2a โ 1)
โ Show Answers
- 2x + 14
- 4a + 12
- 6y โ 12
- 6m + 15
- 9p โ 36
- 20x
- 16a โ 8
๐ง Did You Know?
200 ร 5 bottles
Expanding brackets is simply multiplying groups.
โญ What You Can Do Now
- โ I know what expanding brackets means.
- โ I can identify how many terms are inside brackets.
- โ I can expand brackets correctly.
- โ I know that 2x is one term.
- โ I can avoid common mistakes.
๐ Well Done!
You can now expand brackets correctly. This skill will help you simplify expressions, solve equations and understand factorisation.
๐ง Let’s Think Together
Before calculating, identify the information given, the result required and the mathematical relationship that connects them. Predict whether the answer should be larger, smaller or unchanged, then use that prediction to check the result.
๐ Your Progress
Lesson 7 of 22
Exam Focus
Show the mathematical relationship you are using, keep notation consistent and give a clear final answer. Use a quick estimate, diagram or inverse operation to check that the result is reasonable.
Summary
- Understand the meaning of each idea before selecting a method.
- Use definitions, properties and notation consistently.
- Show working and check that the final result is sensible.