To add negative numbers you need to, forget the signs so how forget the negative sign and just add normally. For example if I add -5 + -3 = -8 so you can observe that in the answer I put a negative sign because a negative + negative = negative.
Now we are going to subtract negative – negative. It is confusing to write it that way so we decide to change the – sign and convert the second number to positive.
Example first: -4 - -5
Example second: -4 + +5
It is much easier to subtract when you change it to addition.
To multiply negative X negative we are going to forget the sings. Then the answer will always be positive so you multiply normally and at last you put the positive sign that is + and that would be your answers.
To divide negative / negative you need to forget the signs . Then you divide normally and the answer will always be positive so you put a + sign (positive sign).

rafa i think you did a great job. I really understood it. and your examples are great. It looks like you took a lot of time creating this blog.
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