Lines making angle 4π with y=3x+5
So using formula tanα=1+m1m2m2−m1, we have slope -2&\frac{1}{2}.
Which are perpendicular to each-other so, A,S,Bare collinear for all a>0. (by property that perpendicular tangents will lie on directrix and chord of contact will pass through focus, so the points are collinear )
