A graph has time (years) on the x-axis and height (inches) on the y-axis. A line goes through points (2, 5) and (4, 10). The graph shows the height of a tree over time. What can you deduce the rate of change to be from 2 years to 4 years ?

Ifound this on google “that means that the graph of a function with direct variation has these features: it is a straight line: because the slope is the ratio y/x = k. it passes through the origin (0,0): because y = kx = k (0) = 0.” i hope this you for what your looking for