In order to find the solution, You would first line line the equation up. then, you would subtract -200 by 15. The answer would be -185. I know the answer will be negative because -200 is too big for 15 to make the solution positive. If you had a positive 201 plus -200 the answer would be equivalent to a positive one because the positive would cancel out the negative.
Included: Negative, positive, equivalent.