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About Geometry Worksheet Assignment 2.19:
Assignment 2.19 is an introduction to two postulates about parallel and perpendicular lines and the definition of distance between a point and a line and between parallel lines.
Prerequisite Skills: Identify and name perpendicular lines (Assignment 2.16). Measure line segments (Assignment 1.11). Identify and name parallel lines (Assignment 1.6).
Postulates: In a plane, there is one and only one line that is perpendicular to a given line through a given point.
In a plane, lines perpendicular to the same line at distinct points are parallel.
Through a point not on a lie, there is exactly one line that is parallel to the line.
Definitions: The distance from a point to a line is the length of a line segment that is perpendicular to the line with endpoints at the point and on the line.
The distance between two parallel lines is the length of a line segment that is perpendicular to the lines with an endpoint on each line.