Find the equation of a line perpendicular to the line `x-2y+3=0`and passing through the point `(1, 2)`.

Explanation

Let the required line be `y=mx+c`


`y=mx+c and x−2y−3=0 are perpendicular`


`m1 times m2 = -1`


` m1=m and m2 ~= y= (1 div 2) times (x-3)`


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