Linked from

The 17 pages that link to Parallel lines, each with the reason it gives.

• Linear perspectiveRelated: Their projected images can converge even though the spatial lines remain parallel.

• Perpendicular bisectorCompared with: Unlike a perpendicular bisector, a parallel line does not cross the segment.

• CollinearityCompared with: Distinct points on parallel lines need not lie on a single shared line.

• EratosthenesRelated: The Sun’s rays were treated as parallel when comparing their angles at the two cities.

• Perpendicular linesCompared with: Parallel lines do not meet, while perpendicular lines intersect at right angles.

• RectangleRelated: Each pair of opposite rectangle sides lies on parallel lines.

• SquareRelated: Each pair of opposite square sides is parallel.

• QuadrilateralRelated: Whether opposite sides are parallel separates parallelograms and trapezoids from other quadrilaterals.

• ParallelogramRelated: The defining condition requires each pair of opposite sides to lie on parallel lines.

• Cavalieri's principleRelated: The planar form uses families of parallel lines to slice figures at corresponding levels.

• TransversalRelated: A transversal crossing parallel lines produces especially useful angle relationships.

• Skew linesCompared with: Unlike skew lines, parallel lines lie in one plane.

• Intercept theoremRelated: Their equal angles with each transversal make corresponding triangles similar.

• Line–line intersectionCompared with: They are the planar case in which two distinct lines have no intersection.

• Playfair's axiomBroader topic: The axiom asserts uniqueness for a parallel through an external point.

• Horizontal line (geometry)Related: Horizontal lines share a direction with the coordinate system's horizontal axis.

• Midpoint theoremNarrower topic: Parallelism is the theorem’s key directional conclusion.