How can I read distance-time graphs?
Distance can be a function of time: d=f(t)
Distance-time graphs are similar to ordinary "y" and "x" graphs.
Replace "y" with "d" and replace "x" with "t". As time changes, distance changes as distance can be a function of time.
Distance can be measured in metres, kilometres or miles and time can be measured in seconds, minutes or hours. Use measurements that are relevant to the problem at hand.