Question

The equation of the lines joining the vertex of the parabola $y^2=6x$ to the points on it whose abscissa are $24$, is

• A. $2y+x+1=0$
• B. $2y-x+1=0$
• C. $x+2y=0$
• D. $x-2y=0$

Answer 1

Answer: (C), (D)

The correct options are
C $x+2y=0$
D $x-2y=0$

Let the point be $P(a,b)$
Given abscissa $=24\Rightarrow a=24$
$\Rightarrow b^2=6\times 24=144\Rightarrow b=\pm 12$
And the vertex of the given parabola is $A(0,0)$
Hence, required lines are $x+2y=0$ or $x-2y=0$