Correct Answer: A
Explanation:
To begin, we can consider each step independently. Because we are only dealing with addition and subtraction, the order we do this in does not matter. Rewrite as follows:
5x+6x−4x−13x=11x−4x−13x
11x−4x−13x=7x−13x
7x−13x=−6x
So there we go, −6x is our answer.