There's two ways of answering this. You can either check if the points marked on the graph matches each option, or you can also get the equation of the line from the graph.
I'll do the second way. To do this we can see that points (3,12) and (1,4) are marked on the line. And we know that the general equation of a line is:
[tex]y=mx+b[/tex]
'm' is the slope and b is the point where the line crosses the 'y' axis. We can see from the graph that b = 0, since the line goes through the origin. So our equation will be something like this:
[tex]y=mx[/tex]
Finally, to find the slope we use the points. If we have two pair of points (x1,y1) and (x2,y2), the slope is:
[tex]m=\frac{y_2-y_1}{x_2-x_1}[/tex]
In this case, this is:
[tex]m=\frac{12-4}{3-1}=\frac{8}{2}=4[/tex]
So, the equation for this graph is:
[tex]y=4x[/tex]
