Since, the line l meets the circle x2+y2=61 at two points A and B.
∵PA=PB=10 ∴PM is perpendicular to AB and OM is perpendicular to the chord AB, therefore line OP is perpendicular to AB. ∴ The slope of line PO is −‌
6
5
. Now, taking option (c). Let the required line be 5x−6y+11=0 its slope is ‌