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Name: michael j stevenson
Status: N/A
Age: N/A
Location: N/A
Country: N/A
Date: Around 1995


Question:
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.


Replies:
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.

chaffer



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