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 )
The distance along a line is undefined until a unit distance, such as. 1 inch or 1 centimeter, is chosen. You can use a ruler to find the. distance between two points on a line. The distance is the. absolute value of the difference of the numbers on the ruler that. correspond to the two points. This distance is the length of the. segment determined by the points.