Directed numbers Addition and Subtraction Examples of Negative
Directed numbers: Addition and Subtraction
Examples of Negative numbers
Examples of Negative numbers
Examples of Negative numbers Thermometers
Examples of Negative numbers Number lines
Addition and subtraction How to explain that: 5 +(– 4)= 1 – 5 –(+4)= 9 5 –(– 4)= 9 – 5 –(– 2)= 3
5+(– 4) = 1 +1 =1 +1 1 1 =0 Zero bank
5 – (+4) = 1 +1 =1 +1 1 1 =0 Zero bank
– 5 – (+4) = – 9 +1 1 =0 Zero bank = – 9 +1 1
– 5 + (+4) = – 1 +1 1 1 =0 Zero bank
5 – (– 4) = 9 +1 1 =0 Zero bank =9 +1 1
4 – (– 5) = 9 +1 1 =0 Zero bank =9 +1 1
– 5 – (– 2) = – 3 +1 1 =0 Zero bank
Subtraction: Using the number line Note the following two rules/principles. 1 st a b gives the difference between a and b 2 nd Large Small positive answer Small Large negative answer
Subtraction: Using the number line Large – small + Example: (4) – (– 6) = 10 +ve 10
Subtraction: Using the number line Small – Large 6 Example: (– 8) – (– 2) = 6 ve
Subtraction: Using the number line Small – Large Example: (– 7) – (5) = 12 ve 12
Subtraction: Using the number line Large – Small 14 + Example: (6) – (– 8) = +ve 14
Addition and subtraction game http: //nrich. maths. org/9941
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