The equation of the vertical line is 
Explanation:
It is given that the vertical line passes through the points 
For vertical line, the slope is undefined.
Hence, 
Let us substitute the coordinate
in the equation
, we have,

Simplifying, we have,


where
and 
Substituting the values of a, b and c in the equation
, we have,

Thus, the equation of the vertical line is 
The correct answer is C. Randomizing the groups and calculating the means and difference of the means.
Hi
You can choose to points (x,y) which solve the equation, like (0,-3) and (4,0) and then draw a line through the points.