A line is related to a surface as a point to a plane. In geometry, a point has no dimensions and defines a location in space, while a plane is a two-dimensional surface that extends infinitely in all directions. Similarly, a line is a one-dimensional figure that extends infinitely in two opposite directions, while a surface is a two-dimensional figure that extends infinitely in all directions.
A Line
A ray starts at a point and extends forever in ONE direction. A line starts at a point and extends forever in TWO directions.
up and down it is the y axis on a graph
line
It extends in both directions (up and down) such that it is parallel to the y-axis.
x = 1 is a graph of a straight line that touches the x-axis at 1 and extends infinitely up and down.
Two. If it were more than two it wouldn't be a line.
A Line
Two, as it is a line.
A ray (line extends in both directions and line segment has two endpoints)
line
It is a vertical line.
A line (a line extends forever in both directions).
The imaginary line that extends straight out from the center of a reflective surface is the optical axis.
A ray starts at a point and extends forever in ONE direction. A line starts at a point and extends forever in TWO directions.
up and down it is the y axis on a graph