en.wikipedia.org/wiki/Perpendicular

In elementary geometry, the property of being perpendicular (perpendicularity) is the relationship between two lines which meet at a right angle (90 degrees). The property extends to other related geometric objects. A line is said to be perpendicular to another line if the two lines intersect at a ... For example, by counting links, three pieces of chain can be made with ...

www.mathsisfun.com/perpendicular-parallel.html

Perpendicular and Parallel. Perpendicular. It just means at right angles (90°) to. The red line is perpendicular to the blue line in each of these examples:.

www.khanacademy.org/math/basic-geo/basic-geo-angle/angles-between-lines/v/identifying-parallel-and-perpendicular-lines

... never intersect. Perpendicular lines are lines that intersect at a right (90 degrees) angle. ... So, for example, line ST is perpendicular to line CD. So line ST is ...

www.montereyinstitute.org/courses/Algebra1/COURSE_TEXT_RESOURCE/U04_L2_T2_text_final.html

Perpendicular lines are two or more lines that intersect at a 90-degree angle, like the two lines drawn on this graph, and the x and y axes that orient them.

www.homeschoolmath.net/teaching/g/parallel_and_perpendicular.php

This lesson explains what are parallel and perpendicular lines and has varied ... For example, l ∥ m means l is parallel to m, and AB ⊥ CD means AB is ...

www.icoachmath.com/math_dictionary/parallel_and_perpendicular_lines.html

Parallel Lines are distinct lines...complete information about parallel and perpendicular lines, definition of an parallel and perpendicular lines, examples of an ...

www.icoachmath.com/math_dictionary/perpendicular_bisector.html

Perpendicular Bisector is a perpendicular line...complete information about perpendicular bisector, definition of an perpendicular bisector, examples of an ...

www.splashmath.com/math-vocabulary/geometry/perpendicular-lines

Definition of Perpendicular Lines explained with illustrated examples. Also, practice lots of math problems with fun math worksheets at Splash Math.

study.com/academy/lesson/what-are-perpendicular-lines-definition-meaning-quiz.html

Aug 29, 2015 ... In trigonometry, for example, perpendicular lines and properties of triangles can be used to calculate height and distances. If the objects used in ...

study.com/academy/lesson/perpendicular-slope-definition-examples.html

Review what perpendicular lines are and what the slope of a line is. Learn about the relationship between slopes of perpendicular lines through...