The distance d of a point P to the line through points A and
     The distance d of a point P to the line through points A and B is the length of the component of  - AP that is orthogonal to  - AB, as indicated in the diagram.  So the distance from P  =  (1, 5) to the line through the points A  =  ( - 2, 2) and B  =  ( - 4, 4) is  . 
  
  Solution
eqn of line passin through A and B is
 
 y -2 = 2 ( x+2)
 2x -y +6 =0
 
 it passes through P (1,5)
 
 distance= 3/5 = 1.3416

