Question

what equation would allow you to land this plane on the runway

Answer 1

To find the equation that represent the land of the plane (the blue line) we have to find the slope and the interseccion with the y axis.

So in the graph we can see that the intersection is:

$c=-7$

Now to find the slope que can use the green points that made a parallel line to the blue line, so with the coordinates (8,-2) and (10,-1) we can use this equation:

$m=\frac{y_2-y_1}{x_2-x_1}$

and we replace the coordinates so:

$m=\frac{-1-(-2)}{10-8}=\frac{1}{2}$

So the final equation will be:

$\begin{gathered} y=mx+c \\ y=\frac{1}{2}x-7 \end{gathered}$