The line through the points (h, 3) and (4, 1) intersects the line `7x-9y-19=0`at right angle. Find the value of h.

Explanation

Condition for bisection of two lines perpendicularly is  m₁m₂=-1

so the slope of a line with 2 given points is (y₂=y₁)/(x₂-x₁)

given points are  (x₁,y₁)=(h,3)    ,   (x₂,y2)=(4,1)

Now,put values in above formula of slope

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