# Using Properties of Perpendicular Lines

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## Perpendicular Lines

A pair of lines that intersect at a right angle are said to be perpendicular.

## Perpendicular Postulate

The perpendicular postulate states that for a point $P$ not on the line $l,$ there exists only one line perpendicular to $l$ that passes through $P.$

This postulate is one of the very basic truths used when proving and finding further characteristics of perpendicular lines.

## Shortest Distance from a Point to a Line

The shortest distance from a point $P$ to a line $l$ is always along the line perpendicular to $l$ through $P.$

## Perpendicular Bisector

The perpendicular bisector of a segment $\overline{AB}$ is the line that is perpendicular to $\overline{AB}$ and intersects $\overline{AB}$ at its midpoint.

## Exercises

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