References: 1  Royal College of Radiologists. 2  Swinson S, Tapp M, Brindley R, Chapman S, Offiah A, Johnson K. An audit of skeletal surveys for suspected non-accidental injury following publication of the British Society of Paediatric Radiology guidelines. 3  Offiah AC, Hall CM.
The question of distance between two straight lines arises only when they are parallel. The given lines are parallel. If the equations of parallel lines are ax + by + c = 0 and ax + by + c' = 0, then the perpendicular distance between them is given by. p = l c - c' l / sqrt ( a^2 + b^2 )
This equal length is called the distance between two parallel lines. Axiom 1. If a ray stands on a line, then the sum of two adjacent angles so formed is 180Âº. Conversely if the sum of two adjacent angles is 180Âº, then a ray stands on a line (i.e., the non-common arms form a line). Axiom 2. If the sum of two adjacent angles is 180Âº, then the non-common arms of the angles form a line.