(2)

let the straight line is... (y-k) = m(x-h)

 

so m= (y-k)/(x-h)

 

noe the line perpendicular to this line have slope.. = - ( x-h)/(y-k)

 

so equation of the perpendicular:

 

       y = - [(x-h)/(y-k) ] x

=>   x²+ y² - hx - ky =0.................(answer )