it means decreasing a number from another no.
the sign is (-)..we call it MINUS
10 - 5 = 5
24 - 6 = 18
so we decrease the no. which is after the minus sign with the number before the sign.
Subtraction Of Integers
because if we subtract 20 from 40 we get 20 so we are right now subtracting 40 from 20 so the answer would be with a minus or negative sign
hope it helps
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