The standard form of equation of a line is expressed as y = mx+c
m is the slope
c is the y intercept
Note that the line does not have a slope and the x intercept of the line is a point where the line cuts the x axis. Hence the equation of the line will be expressed as x = c where c is the x intercept;
<em>From the graph, the x intercept =9. Hence the equation of the given line is x = 9</em>