For me that subtracting a negative number becomes addition is currently magic. I have watched and read a number of "explanations" and they all basically boils down to:     -- = +   Which for me is magic!  None of these sources have been able to give me a logical and mentally understandable explanation about how exactly subtracting a negative number becomes addition.  As a frame of reference, the below makes sense:     2 + (-4) = -2   For me this is logical. It that tells that the number to add starts at a minus, a deficit.  However how:     2 - (-4)   becomes     2 + 4   is beyond my current understanding of how math works.  The closest I can get is that negative + negative is somehow turning into positive. But that to me is currently just a magical rule.  I think I have missed something very important here, something that makes what I at the moment see as illogical for others clearly is logical and makes perfect sense.  I would be immensely grateful to the person who will take their own time to explain to me how this works, because right now I am very stuck.
Why subtraction of a negative number from a positive number is addition? Eg: $a - (-b) = a + b$ When looking through the number scale I am unable to relate this, please kindly clarify ?
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