Could a tutor please help me to find an equation
that goes through (4,0) and (4,4) 
Thank you for your assistance!!

Plot the two points 

 

Draw a straight line through those two points:




It's vertical so that means that every point
on the graph has its x-coordinate as 4. So
the equation is just simply:

    x = 4

That's all there is to the equation of a 
vertical line.

Edwin