If the ends of a focal chord of the para...

If the ends of a focal chord of the parabola `y^(2)=8x` are `(x_(1),y_(1)) and (x_(2),y_(2))`, then `x_(1)x_(2)+y_(1)y_(2)` is equal to a)12 b)20 c)0 d)-12

A

12

B

20

C

0

D

`-12`

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The correct Answer is:

D

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