Point/line distance formula
Name: michael j stevenson
Date: Around 1995
I am looking for a formula that will tell me the distance between a point
and a line. Someone told me that it was Ax + By + C/A^2 + B^2, but I am not
sure if it is right or not. I know that if you find the perpendicular line
that goes through the point and solve for the intersection of the two lines,
you have two handy points you can use with the traditional distance formula,
but I need something faster.
The formula you give is close, but not quite correct. For a line with
equation Ax + By + C = 0 and a point (r,s) the distance from the point to
the line is given by abs(Ar + Bs + C)/sqrt(A^2 + B^2). Here abs denotes
absolute value and sqrt denotes square root.
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