For a line to be parallel to the y-axis we need either 1 of 2 things.grandh01 wrote:Is line l parallel to the y-axis?
(1) The equation of line l is x = 4.
(2) The points (4. 2) and (4, - 5) are
on line l .
1. The equation of the line needs to be x= some number or 2. The slope needs to be undefined (or vertical).
Lets look at the statements:
1. x=4. This is sufficient for reasons stated above. You can also visualize this. Draw the line x=4 and you will see that it is indeed parallel.
2. (4, 2) and (4, - 5). If you plot these points you see that the slope is undefined as it is a vertical line. This is also sufficient.
The correct answer is D
Let me know if this helps
