Q. The point of the parabola $y^{2} = 18x$, for which the ordinate is three times the abscissa, is
A) $(6,\ 2)$
B) $( - 2,\ - 6)$
C) $(3,18)$
D) $(2,\ 6)$
Explanation
(d)
Let $x$ be any point on the parabola, then $y = 3x$, putting this value in the given equation $y^{2} = 18x$, we get
${(3x)}^{2} = 18x\ \Rightarrow x = 2$ and $y = 6$
Reviewed by Dr. Abubacker
Physics Educator & NEET/JEE Specialist
Ph.D. in Physics with 19+ years of teaching experience.