The subtraction of a negative number is the same as addition of the
positive equivalent of the number.
The outputs of the operations are;
Reasons:
(a) The operation is -2 - (-9)
Which is the subtraction of negative 9 from negative 2, which gives, a double negative, which is equivalent to a positive, therefore, we get;
-2 - (-9) = -2 + 9 = 7
(b) The operation is -2 - 9
The above operation is the subtraction of +9 from negative 2, which gives;
-2 - 9 = -11
(c) The operation is -2 - (-9) - (-2)
The above operation is the subtraction of negative 9, and negative 2 from
negative 2, and therefore, has two double negatives that result two
positive(s) increases, as follows;
-2 - (-9) - (-2) = -2 + 9 + 2 = 9
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