Here is your answer, you just count to 10... Simple as that.
So say for example u have -7 - (-5), think of subtracting integers as adding the opposite, so ur adding the opposite of -5, the opposite of -5 is 5, so ur adding -7 and 5= -2
another one: -15 - (-18)
again, adding the opposite. -15 plus positive 18= 3
It is divisible by 1, 2, 3, 4, 5, 6, 8, 10
