Transcript File - Luluk Sofijati

KS3 Mathematics
N2 Negative numbers
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Contents
N2 Negative numbers
A N2.2 Adding and subtracting integers
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Multiplying and dividing integers – Starter
Starter - Complete the following:
–3 × 8 = –24
–36 ÷
42 ÷
54
–7 = –6
= –4
÷ –9 = –6
–11 × –8 = 88
–7 × –15 = 105
47 ×
–4 × –5 × –8 = –160
2
= 94
–72 ÷ –6 =
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9
12
3 × –8 ÷ –10 = 2.4
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Adding integers
We can use a number line to help us add positive and
negative integers.
–2 + 5 = 3
-2
3
To add a positive integer we move forwards up the
number line.
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Adding integers
We can use a number line to help us add positive and
negative integers.
–3 + –4 = –7
-7
-3
To add a negative integer we move backwards down the
number line.
–3 + –4 is the same as
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–3 – 4
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Subtracting integers
We can use a number line to help us subtract positive and
negative integers.
5 – 8 = –3
-3
5
To subtract a positive integer we move backwards down
the number line.
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Subtracting integers
We can use a number line to help us subtract positive and
negative integers.
3 – –6 = 9
3
9
To subtract a negative integer we move forwards up the
number line.
3 – –6
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is the same as
3+6
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Subtracting integers
We can use a number line to help us subtract positive and
negative integers.
–4 – –7 = 3
-4
3
To subtract a negative integers we move forwards up the
number line.
–4 – –7
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is the same as
–4 + 7
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Adding and subtracting integers summary
To add a positive integer we move forwards up the
number line.
To add a negative integer we move backwards down the
number line.
a + –b is the same as a – b.
To subtract a positive integer we move backwards down
the number line.
To subtract a negative integer we move forwards up the
number line.
a – –b is the same as a + b.
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Exercise A
Work out the following
1) –5 + 7
9) 3 – 6
2) – 3 + 5
10)– 2 – 3
3) – 6 + 9
11) – 3 – 3
4) 4 – 6
12) 0 – 5
5) +5 – 6
13)1 + 4 – 6
6) 4 – 10
14) 5 – 11 – 2
7) 2 – 6
15)– 8 + 6
8) 3 – 3
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Exercise B
Work out the following
1) – 8 + 9
9) 5 – 9
2) – 6 + 10
10) – 8 + 8
3) – 2 + 8
11)6 – 12 – 4
4) 0 – 8
12)7 – 10 + 3
5) 3 – 10
13)– 3 + 10 – 7
6) 8 – 10
14) 6 – 12 + 6
7) 7 – 9
15)8 – 16 – 3
8) 4 – 10
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Exercise C
Work out the following
1) 4 + – 2
2) 2 + – 3
3) 4 – –2
4) 5 – – 4
5) 15 – – 3
6) 4 – – 6
7) – 9 – – 5
8) – 10 + – 7
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Exercise D
Ten Ticks. Level 5. Pack 4. Page 3
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Exercise E
Ten Ticks. Level 5. Pack 4. Page 3
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Ordered addition square
Copy the grid and work out the numbers in the empty squares
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Mixed addition square
Copy the grid and work out the numbers in the empty squares
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Ordered subtraction square
Copy the grid and work out the numbers in the empty squares
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Mixed subtraction square
Copy the grid and work out the numbers in the empty squares
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Complete this table
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Integer cards - addition and subtraction
Complete the sums
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Adding and subtracting integers summary
To add a positive integer we move forwards up the
number line.
To add a negative integer we move backwards down the
number line.
a + –b is the same as a – b.
To subtract a positive integer we move backwards down
the number line.
To subtract a negative integer we move forwards up the
number line.
a – –b is the same as a + b.
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