https://www.khanacademy.org/math/geometry/hs-geo-analytic-geometry/hs-geo-parallel-perpendicular-lines/v/parallel-and-perpendicular-lines-intro 2021-06-30T20:49:34Z Parallel & perpendicular lines intro Parallel lines never intersect, and perpendicular lines intersect at a 90 degree angle. Learn how to identify parallel and perpendicular lines. Sal Khan video https://cdn.kastatic.org/googleusercontent/CRTGzDu0cHddrkhiOFmwrkf50_2Kd0kMEh9xECcGSiBHgA0RMavpcbIUUkOTzPKm6jUKCuCa1fUipy280HvNtevJEQ Parallel & perpendicular lines intro Parallel lines never intersect, and perpendicular lines intersect at a 90 degree angle. Learn how to identify parallel and perpendicular lines. https://cdn.kastatic.org/ka-youtube-converted/V0xounKGEXs.mp4/V0xounKGEXs.mp4 128 Parallel & perpendicular lines on the coordinate plane https://www.khanacademy.org/math/geometry/hs-geo-analytic-geometry/hs-geo-parallel-perpendicular-lines/v/classify-lines 2022-09-10T02:03:40.164764806Z Parallel & perpendicular lines from graph The slopes of parallel lines are equal, and the slopes of perpendicular lines are opposite reciprocals. This is a worked example of determining whether given lines are parallel or perpendicular. video https://cdn.kastatic.org/ka_thumbnails_cache/ccf3cc05-28e0-459b-b6d1-521eaf05413c_1280_720_base.png Parallel & perpendicular lines from graph The slopes of parallel lines are equal, and the slopes of perpendicular lines are opposite reciprocals. This is a worked example of determining whether given lines are parallel or perpendicular. https://cdn.kastatic.org/ka-youtube-converted/6riBTnlI4fw.mp4/6riBTnlI4fw.mp4 446 Parallel & perpendicular lines on the coordinate plane https://www.khanacademy.org/math/geometry/hs-geo-analytic-geometry/hs-geo-parallel-perpendicular-lines/e/classifying-lines-as-parallel--perpendicular--or-neither 2026-03-19T10:07:17.424260476Z Parallel & perpendicular lines from graph Given points that two lines go through or the graph of each line, classify the lines as parallel, perpendicular, or neither. . exercise https://www.khanacademy.org/math/geometry/hs-geo-analytic-geometry/hs-geo-parallel-perpendicular-lines/v/classfying-a-quadrilateral-on-the-coordinate-plane 2021-04-21T17:08:26Z Classifying quadrilaterals on the coordinate plane Watch Sal classify a quadrilateral as a square, rhombus, rectangle, parallelogram, or trapezoid given its four vertices. Sal Khan video https://cdn.kastatic.org/googleusercontent/4xHgj50OcXE4kBDlCRGRb9QUwrwd501oBlFjW53sOtHBqDonB_8ev6TWOvaTwEoUaXX2oh_p5EF299jFSvB6cuqq Classifying quadrilaterals on the coordinate plane Watch Sal classify a quadrilateral as a square, rhombus, rectangle, parallelogram, or trapezoid given its four vertices. https://cdn.kastatic.org/ka-youtube-converted/vsgrWDLEzcQ.mp4/vsgrWDLEzcQ.mp4 308 Parallel & perpendicular lines on the coordinate plane https://www.khanacademy.org/math/geometry/hs-geo-analytic-geometry/hs-geo-parallel-perpendicular-lines/v/classifying-figures-with-coordinates 2022-09-10T02:03:40.164764806Z Classifying figures with coordinates Use coordinates to determine the slopes of sides of a figure in order to classify it. Sal Khan video https://cdn.kastatic.org/ka_thumbnails_cache/277fe497-892a-47db-b339-fceb3efdc2e1_1280_720_base.png Classifying figures with coordinates Use coordinates to determine the slopes of sides of a figure in order to classify it. https://cdn.kastatic.org/ka-youtube-converted/2B5SQba9xSo.mp4/2B5SQba9xSo.mp4 417 Parallel & perpendicular lines on the coordinate plane https://www.khanacademy.org/math/geometry/hs-geo-analytic-geometry/hs-geo-parallel-perpendicular-lines/e/classify-figures-by-coordinates 2026-05-12T20:51:02.525826344Z Classify figures by coordinates Given the coordinates of a quadrilateral or triangle, determine whether it has the features necessary to be a specific kind of shape, such as a rectangle. exercise