Equation of a vertical line

The equation of a vertical line is:

$x=$ The same number

Example

$x = 7$

No matter what value y is, x is 7.

$y = 2$ $x = 7$

$y = 1$ $x = 7$

$y = 0$ $x = 7$

$y = -1$ $x = 7$

$y = -2$ $x = 7$

The graph would be plotted as follows.

Plot a vertical line on the graph which goes through the x axis

And would look like this.

Now find the x axis value and y axis value x = 7

This is a vertical line.