Answer 1

The line perpendicular to lx + my + n = 0 is \[mx - ly + \lambda = 0\]

This line passes through (α, β). 

\[\therefore m\alpha - l\beta + \lambda = 0\]

\[ \Rightarrow \lambda = l\beta - m\alpha\]

Substituting the value of \[\lambda\]: 

\[mx - ly + l\beta - m\alpha = 0\]

\[ \Rightarrow m\left( x - \alpha \right) = l\left( y - \beta \right)\]

This is equation of the required line.