WHat is a perpendicular line? is anyone here? earth to Jiskha you here???

Answer 1

there is no such thing as a perpendicular line by itself. It must be perpendicular to something else.

For example, the character ⊥ shows two perpendicular lines.
a flagpole illustrate a line perpendicular to a plane.

while you were waiting here, did you bother to google the term, or look it up in your math textbook?