Identify Numbers and Operation: Identify the numbers and the operation.We have the number 3 and we need to subtract −6 from it.Subtraction of a negative number is the same as addition of the positive equivalent of that number.
Rewrite Subtraction as Addition: Rewrite the subtraction of a negative number as an addition.3−(−6) is the same as 3+6 because subtracting a negative is the same as adding a positive.
Perform Addition: Perform the addition. 3+6 equals 9.