Question

$P$ is a point on $y^2=4ax(a>0)$ whose vertex is $A$. $PA$ is produced to meet the directrix in $D$ and $M$ is the foot of perpendicular from $P$ on the directrix. If a circle is described on $MD$ as a diameter then it intersects $x-$axis at

• A. $(–3a,0)$
• B. $(–2a,0)$
• C. $(a,0)$
• D. $(–a,0)$

Answer 1

Answer: (A), (C)

The correct options are
A $(–3a,0)$
C $(a,0)$

The circle will cut the $x-$axis at $(–3a,0)$ and $(a,0)$.