If a line is horizontal, it will have a equation that is y = C, being C a constant.
Then, if the line is horizontal and goes through (3,-2), we can conclude that the equation is:
Then, for any value of x, the point will be (x,-2).
The point (5,k) will have to be (5,-2). The value of k has to be k=-2.
We can graph this as:
Answer: k=2