Jason and Hilger are required to paint over the graffiti on a wall. If Jason worked alone, it
would take him 20 h to repaint. Working alone, Hilger could do the job in
15 h. How long
will it take them to do the painting if they work together?

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