Answer:
A. It is the equation of a horizontal line.
Step-by-step explanation:
The line, whose equation is x = 4 , is vertical on a certesian plane and not horizontal.
Its slope is udefined because any number devided by zero give undefined result.
The point (4, 7) lies on the line.
It is perpendicular to y = 6.
Attached graph:
The red line represents the line whose equation is x = 4
The blue line represents the line whose equation is y = 6
