Addition and Subtraction Properties
Something about Addition
Commutative Property
The first thing you should know about Addition is that the order of adding is not important.
They even have a complicated name for it: Commutative Property.
Here, look at this:
You see? When we add the numbers  we get the same result on both sides:
Associative Property
The same goes for 3 or more numbers. You can add in any order you like  you'll get the same result.
This one is called (don't try to remember it): Associative Property.
Here, we start the same on both sides:
but group (add) numbers differently:
and at the end  we get the same result:
Adding a zero
Finally, adding a zero  is actually adding noting  or more accurately not adding anything:
Something about Subtraction
OK, let's see what applies to Subtraction.
Here, check this out:
Subtraction  Addition connection
Then see this:
Do you see? This is why:
And that is the conneciton between Addition and Subtraction.
Subtracting a zero
And of course, subtracting a zero from a number makes no difference also:
If we take away zero = nothing, then we did not take anything. :)
