Would someone be kind enough to tell me what the rules are for operations involving negative numbers?
For instance is it correct that adding two negatives makes a positve?
Thanks
go to the link ...
Amby's Math Resources - Integers: Operations with Signed Numbers
The confusion arrises when you hear at school (by a teacher not thinking about how students interpret their info) that two negatives make a positive (bad teacher)
Now that sounds fine on the surface because -2 x -6 = + 12.
But students then switch off their brains and think
-4 - 6 = + 10 : here you have to ignore rules of signs and add up : lose 4 then lose 6 - i have lost 10 (-10)
Put simply: WHEN multiplying or dividing
Signs the same -> positive answer
Signs different -> negative answer
WHEN adding or taking
(when 2 signs appear together, if the same sign make into a + other wise make into a -)
EG: 2 - -4 = 2 + 4 = 6 EG -2 -4 = -6