Expanding single brackets
The Maths Habit
1Simplify x + x + x
3x
2How many squares?
12
3Write 5 × x with no × sign
5x
Every party bag gets what is in the first bag. Sam buys this to fill the bags. Has Sam got enough?
No. Every bag needs its sweets too.
- Term
- One part of an expression. Terms are joined by + or − signs.
- Bracket
- Holds terms together. A number in front of it multiplies everything inside.
- Expand
- Multiply out the bracket, so there is no bracket left.
Expand 3(x + 2)
3 rows of x + 2
×1Split the bracket
x+233 on the side. x and +2 on top.
2Multiply each part
3x+63 bars make 3x. 6 squares make +6.
Answer3x + 6
How many x bars? How many squares?
2 x bars and 8 squares
Which is right?
5(x + 2)5x + 25x + 10
5x + 10: multiply each part
Expand 4(x + 6)
1Split the bracket
×x+62Multiply each part
44x+24Answer4x + 24
Expand 2(x + 6)
1Split the bracket
×x+62Multiply each part
22x+12Answer2x + 12
Expand 4(x + 6)
1Split the bracket
×x+62Multiply each part
44x+24Answer4x + 24
Expand 5(x + 3)
1Split the bracket
×x+32Multiply each part
55x+15Answer5x + 15
Remember1Split the bracket2Multiply each part
Expand 4(x + 6)
1Split the bracket
×x+62Multiply each part
44x+24Answer4x + 24
Expand 3(x + 4)
1Split the bracket
×x+42Multiply each part
33x+12Answer3x + 12
Remember1Split the bracket2Multiply each part
Expand 4(x + 6)
1Split the bracket
×x+62Multiply each part
44x+24Answer4x + 24
Expand 2(x + 10)
1Split the bracket
×x+102Multiply each part
22x+20Answer2x + 20
Remember1Split the bracket2Multiply each part
Expand 2(x + 8)
Answer2x + 16
Expand 3(x + 5)
Answer3x + 15
Expand 5(x + 6)
Answer5x + 30
Remember1Split the bracket2Multiply each part
- A dashed square takes away 1.
- 4(x − 3) is 4 rows of x − 3.
- Keep the − with the 3 on top of the grid: −3.
What goes on top of the grid?
3(x − 4)
x and −4
Expand 4(x − 3)
1Split the bracket
×x−32Multiply each part
44x−12Answer4x − 12
Expand 2(x − 5)
1Split the bracket
×x−52Multiply each part
22x−10Answer2x − 10
Expand 4(x − 3)
1Split the bracket
×x−32Multiply each part
44x−12Answer4x − 12
Expand 5(x − 2)
1Split the bracket
×x−22Multiply each part
55x−10Answer5x − 10
Remember1Split the bracket2Multiply each part
Expand 4(x − 3)
1Split the bracket
×x−32Multiply each part
44x−12Answer4x − 12
Expand 3(x − 6)
1Split the bracket
×x−62Multiply each part
33x−18Answer3x − 18
Remember1Split the bracket2Multiply each part
Expand 4(x − 3)
1Split the bracket
×x−32Multiply each part
44x−12Answer4x − 12
Expand 4(x − 7)
1Split the bracket
×x−72Multiply each part
44x−28Answer4x − 28
Remember1Split the bracket2Multiply each part
Expand 2(x − 3)
Answer2x − 6
Expand 5(x − 6)
Answer5x − 30
Expand 3(x − 8)
Answer3x − 24
Remember1Split the bracket2Multiply each part
Is the answer right? Thumbs up: yes. Thumbs down: no.
4(x + 4) = 4x + 16
Yes
5(x + 1) = 5x + 1
No: 5x + 5
2(x − 4) = 2x + 8
No: 2x − 8
10(x + 5) = 10x + 50
Yes
3(x − 3) = 3x − 9
Yes
Find the missing number. 3(x + □) = 3x + 21
7
Expand 4(2x + 3)
8x + 12
Write a bracket that expands to 6x + 12. Can you find two?
6(x + 2) or 3(2x + 4)
Expand 2(x + 7). Step 1 is given: 2 on the side, x and +7 on top.
Answer 2x + 14
Expand 5(x − 3)
Answer 5x − 15
Expand 10(x + 4)
Answer 10x + 40
Exit tickets to print