Answer: 14
Work: First, we must get rid of the four from the side it's currently on. So, we are going to add it on both sides. After adding four on both sides, I'll cancel on the side it was on, and the new equation is -126 = -9k. Now, we are going to divide -9 on both sides and yet again, I'll cancel on the side it was on. The answer is k = 14. It's a positive 14 because we divided a negative by a negative, and after doing so, the new number is a positive.
I hope this helps, and Happy Holidays! :)