Download Negative numbers - Great Maths Teaching Ideas

MathsMemoryCards
Set15- Negativenumbers
Negativenumbers
are…
Numbersgetlower
thefurther…
Sometimesnegative
numbersarewritten…
We don’tusethe
word…
Negative numbers
Whenyoumultiply or
(thoselessthanzero)
divide apositive
areshownusinga‘–’
numberby apositive
sign.Positive
number…
numbers…
Whenyoumultiply or Whenyoumultiply or
divide apositive
divide anegative
numberby anegative numberby apositive
number…
number…
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MathsMemoryCards
Set15- Negativenumbers
…leftyoumovedown
thenumber line.-5is …thoselessthanzero
lowerthan-2
onthenumberline
Lower
-5
Higher
-4
-3
-2
-1
0
1
2
…’minus’. Weusetheword
…in brackets.This
‘negative’instead.The
doesn’tchangethe
number3below0is
’negativethree’,not‘minus number.-3and(-3)
arethesamenumber
three’
…yougetapositive
answer.
3X4=12
30÷ 6=5
…arethoseabovezero.
Usuallywedon’tusea‘+’
signtoshowtheyare
positive.Wejustwritethe
number,but+3and3are
thesamenumber
…yougetanegative
answer.
…yougetanegative
answer.
-3X4=-12
-30÷ 6=-5
3X-4=-12
30÷ -6=-5
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MathsMemoryCards
Set15- Negativenumbers
Whenyoumultiply or
divide anegative
numberby anegative
number…
3+2 =?
-2+5 =?
-4+3 =?
5−3 =?
3−4 =?
-2−3 =?
Adding anegative
number…
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MathsMemoryCards
Set15- Negativenumbers
3+2 =5
Startat3,moveup
thenumberline2
-1
0
1
2
3
4
5
…yougetapositive
answer.
6
-4+3 =-1
Startat-4,moveup
thenumberline3
-5
-4
-3
-2
-1
0
1
-3X-4=12
-30÷ -6=5
2
-2+5 =3
Startat-2,moveup
thenumberline5
-3
-2
-1
0
1
2
3
4
3−4 =-1
5−3 =2
Startat3,movedown Startat5,movedown
thenumberline4
thenumberline3
-2
-1
0
1
2
3
4
5
1
0
1
2
3
4
5
6
…isthesameasdoing
-2−3 =-5
Startat-2,movedown the
asubtraction.
numberline3
3+-2
isequivalentto
3− 2
-6 -5 -4 -3 -2 -1 0
1
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MathsMemoryCards
Set15- Negativenumbers
Subtracting anegative
number…
3+-2 =?
5+-7 =?
-4+-3 =?
5−-3 =?
-3−-4 =?
-5−-3 =?
Squaring anegative
number…
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MathsMemoryCards
Set15- Negativenumbers
3+-2
…isthesameasdoing
isequivalentto
anaddition.
3− 2=1
3− -2
Startat3,movedown
isequivalentto
thenumberline2
3+ 2
5+-7
-4+ -3
is equivalentto
isequivalentto
-4− 3=-7
5− 7=-2
Startat-4,movedown the Startat5,movedown
numberline3
thenumberline7
-3−-4
is equivalentto
-3+ 4=1
Startat-3,moveup
thenumberline4
5−-3
is equivalentto
5+ 3=8
Startat5,moveup
thenumberline3
…givesapositive
answer.
(-3)2 =-3× - 3=9
-5−-3
isequivalentto
-5+ 3=-2
Startat-5,moveup
thenumberline3
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MathsMemoryCards
Set15- Negativenumbers
It isnot possible…
Saythiscalculation
outloudthenanswer
it:
3× -2
Saythiscalculation
Saythiscalculation
outloudthenanswer outloudthenanswer
it:
it:
-6÷ -2
-4+2
Saythiscalculation
Saythiscalculation
outloudthenanswer outloudthenanswer
it:
it:
-4−2
-3+-5
Saythiscalculation
Saythiscalculation
outloudthenanswer outloudthenanswer
it:
it:
-5−-2
(-4)2
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MathsMemoryCards
Set15- Negativenumbers
’Threetimes negative
twoequalsnegative
six’
…to squareroot a
negativenumberand
getareal number
answer
‘Negative fouradd
twoequalsnegative
two’
‘Negative sixdivided
bynegative two
equals(positive)
three’
‘Negative threeadd
negative fiveequals
negative eight’
‘Negative four
subtract twoequals
negative six’
‘Negative four
squared equals
(positive)sixteen’
‘Negative fivesubtract
negative twoequals
negative three’
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