Problem: What is -16 - (-4)?
When I say this out loud, I might say: "Negative 16 minus negative 4 equals what?"
Is this an add/sub/mult/divide problem?
This is a subtraction problem because we start with a number and then take away another number.
Rewrite the problem using the Subtracting Integers process:
When we subtract a negative number, it's the same as adding the positive version of that number. So, we can rewrite the problem:
-16 - (-4) becomes -16 + 4.
Explanation in words:
We are starting with -16, which is like being $16 in debt. When we subtract -4, we are effectively removing a negative amount. Since subtracting a negative is the same as adding a positive, we add 4 instead. So, really, we're saying: "I have $16 in debt, but I'm getting back $4."
Solve the problem:
Now, let's solve it:
-16 + 4 = -12.
Explanation of the answer's sign:
The answer is -12. This means that after adding 4 to -16, we still owe $12. The sign of our answer is negative because we started much deeper into debt (at -16) than the amount we added back (which was +4). Even though we added a positive number, it wasn't enough to make the total positive again, so we remain in the negative.
So, the answer to -16 - (-4) is -12.
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