Browse Questions

# The tangents at the end of any focal chord to the parabola $y^{2}=12x$ intersect on the line

$\begin{array}{1 1}(1)x-3=0&(2)x+3=0\\(3)y+3=0&(4)y-3=0\end{array}$

The tangent at the end of any focal chord to the parabola intersect on the directrix.
The equation of the parabola is $y^2=12x$
$y^2=4(3)x=>a=3$
The equation of the directrix is
$x=-3$
ie $x+3=0$
Hence 2 is the correct answer.