+(-11) is -11. You're "adding" -11 when in reality you're taking away 11 unless:
the equation looks like: -6+(-11)
the answer would be -17 because you're adding a negative to a negative. Taking away from a negative number is simply moving further down the negative number line, which makes the negative numbers "increase" in value
But if an equation looks like: 6+(-11)
the answer would be -5 since you are taking away 11 from a positive number.
Hope this makes sense and answers your question.
