This is a simple problem! So let’s start. The rule a negative and a negative makes a positive plays a role in here so then we can switch it to -6+9 now subtract 9 to 6 and you get 3. That will be your answer. You can switch the numbers around to make it easier that what I like to do. For example, instead of having -6+9 you could instead do 9-6!
Hope this helps!
If I’m wrong say it in comments I don’t want it to harm others.