The distance "d" you bike varies directly with the amount of time "t" you bike. Therefore,
d α t
To turn it into equality, we introduce k, proportionality constant.
d = kt
We find the value of k from the given conditions. Suppose you bike 13.2 miles in 1.25 hours.
13.2 = k(1.25)
k = 10.8 miles/our
Therefore the equation would be:
d = 10.8t
It is a linear graph with slope 10.8 and it passes at the origin.
