A vertical line is one which runs up and down the page.
In geometry, a vertical line is one which runs from up and down the page.
Its cousin is the
horizontal line which runs left to right across the page. A vertical line is
perpendicular to a horizontal line.
See perpendicular lines.
Vertical angles are different use of the word 'vertical'. Vertical angles are angles that share a common vertex
and need not be drawn one above the other. See Vertical angles.
A line will be vertical if any two points on the line have the same x-coordinate.
See Vertical line (coordinate geometry).
Other line topics
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