Answer: Both graphs are solid lines.
Reasoning:
When the independent variable is continuos and the relation (the equation) is continous then you a graph that is a solid line. When the iindependent variable is discontinuos or the relation is not a continuos function, then the graph will have discontinuities or some unconnected dots.
The
relationship between time and the distance the remaining on a 3-Mile
walk for someone walking at a steady rate of 2 miles per hour.
Given that both, the time (which is the input variable) and the distance remaining for the walk are continuos variables, then all the data are connected and the graph is a continuos line.