we know that
The line [tex]x=4[/tex] is parallel to the y-axis and is perpendicular to the x-axis
therefore
The line [tex]x=2[/tex] is parallel to the line [tex]x=4[/tex] , because is parallel to the y-axis and is perpendicular to the x-axis too
using a graphing tool
see the attached figure
the answer is
[tex]x=2[/tex]