BGCSE CORE
DIRECTED NUMBERS
Numbers can either be positive or negative. The name directed number comes from thinking of a number line. The sign tells which direction from 0 on the number line the number lies: positive numbers on the right and negative numbers on the left.
Brackets are, at times, put around negative numbers to make them easier to read, e.g. (-2). Sometimes a '+' or '-' sign is written in front of the number. Both methods are used and you need to be happy using both. If a number is positive, the + is usually missed out before the number. So 3 is really (+3) or +3. |
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addition and subtractioN
If signs are the same (+), (+) OR (-), (-),you ADD and keep the same sign.
another wayTwo like signs become a positive sign
Eg: 7−(−5) = 7 + 5 = 12 Two unlike signs become a negative sign Eg: 8 +(−4) = 8 − 4 = 4 |
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MULTIPLICATiON AND DIVISION
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