What characteristic of the line makes the behavior of these

Question

First, draw a graph of a line that grows quickly.

Second, draw a graph of a line that grows slowly.

Third, draw a graph of a line that doesn't grow, but instead decreases.

1. What characteristic of the line makes the behavior of these lines different?
2. What is it about that characteristic that determines if the line grows quickly, slowly, or actually decreases?
3. Can you use that characteristic to make a line that neither grows nor decreases? If so, draw it on the fourth graph.
4. What has to be true about that characteristic to be able to make a graph for question