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The focal chord of the parabola y^2=a x ...

The focal chord of the parabola `y^2=a x` is `2x-y-8=0` . Then find the equation of the directrix.

A

`x+4=0`

B

`X-4=0`

C

`Y-4=0`

D

`Y++4=0`

Text Solution

Verified by Experts

The correct Answer is:
A
The coordinates of the focus of the parabola `y^(2)=ax` are (a/4, 0).
It is given that `2x-y-8=0` is a focal chord.
`:." "a/2-8=0rArra=16`.
The equation of the directrix is `x=-a/4" i.e. "x=-4`.
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OBJECTIVE RD SHARMA ENGLISH-PARABOLA-Section I - Solved Mcqs
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  17. In exampla 27, the radius of the incircle of DeltaPQR, is

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