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1. #INTEGERS NEGATIVE AND POSITIVE RULES HOW TO#
2. #INTEGERS NEGATIVE AND POSITIVE RULES FULL#
3. #INTEGERS NEGATIVE AND POSITIVE RULES PLUS#

If you have $7$ hot and combine it with $-6$ (6 cold), then you are still warmer than 0 at $+1$. Now the idea of $-(-1)=1$ is "removing one cold is the same as adding a heat". (Of course this analogy breaks because of absolute zero, but you can get away with it for now.) If you can imagine $+1$ as being a unit of "heat" and $-1$ as being a unit of cold, and $0$ as being room temperature, or freezing or whatever. Somehow I forgot about another obvious version, that of a thermometer.

The $-(-2)$ can be interpreted as "the removal of a debt of 2" which would be the same thing as gaining $+2$.Įlectric charge is another model, but less down to earth than money and dirt, maybe. If you have $-3$ debt and you add $+2$, the combination would be that you still owe $-1$. If you "have" $-1$ dollars, you owe $1$ dollar.

#INTEGERS NEGATIVE AND POSITIVE RULES HOW TO#

Obviously, if they understand how to use money, you can do the same picture but with owned dollars and owed dollars. There are obvious variations of this for children as they grow older.

I guess what I have in mind is really thinking of $+1$ as a box of dirt, $-1$ as a vacancy (hole) of the exact same size as one box of dirt, and the positive numbers as stacks of filled unit boxes, and negative numbers as stacks of "vacancies" of the same size as a box of dirt. Taking away a one box vacancy is the same as filling it in, i.e. So how to deal with $-(-3)$? One can interpret this as "taking away 1-box vacancies". If you have a box of dirt and dump it into a 1-box-hole, it fills perfectly and you get $0$.

#INTEGERS NEGATIVE AND POSITIVE RULES FULL#

If there are no boxes full of dirt and no holes, then we are at 0. If you dig a cubish hole in the ground and use it to fill one box, the empty space is supposed to represent $-1$. You can think of "a box of dirt" as being a unit, and talk about boxes of dirt stacked on top of each other. I remember learning it as a child using something like a "digging a hole" metaphor. PS: I think the tags I added are not right, but thats all I could think of, so if I have gone wrong, do edit that. Please suggest a method that will involve only basic algebra as she is in grade 4.Īslo, if you find an easier way, do share it with me!

So, my question is, How can I better explain it to her? Or rather, does this have any flaw which needs to be corrected? To see if she has really understood, I asked her to explain this to my mother, and the result was not satisfactory. So, that is your answer!īut I think this is a little too long so I said that you should observe this pattern and then use the result $-(-x)=x$ and solve questions. Now, I can say that is the same as $5+0-3-(-3)$ and by the definition of $-3$, $0-3=(-3)$, So now the expression becomes $5 + (-3) - (-3)$ and since $(-3)$ is being added and subtracted, we will just cancel that and write 5.

#INTEGERS NEGATIVE AND POSITIVE RULES PLUS#

So, I did not want to say that because minus of minus is plus, so the answer to b) is 5, and minus of plus is minus, so you can solve a) and c) likewise.and I explained in detail how we can simplify these and for b) particularly, I said: I was trying to teach my younger sister some math, and it drifted on to integers, and operations on negative integers.