Let be a point on the circle a point on the line and the perpendicular bisector of be the line Then, the coordinates of are
Let the coordinates of and be and respectively. Then,
…(i)
and …(ii)
Since PQ is perpendicular to the line
…(iii)
The mid point of PQ lies on
…(iv)
From (iii) and (iv), we get
Substituting x1 , y1 in (ii), we get
Putting the value of h in , we get
Hence, the coordinates of are or,