Prove that the product of the lengths of the perpendiculars drawn from the points 
and 
to the line
The equation of the given line is
⇒ bxcosƟ + aysinƟ – ab = 0 ……………….(1)
Length of the perpendicular from point 
to line (1) is
--------------- (2)
Length of the perpendicular from point 
to line (2) is
--------------- (3)
On multiplying equations (2) and (3), we get,
Hence Proved.
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