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If A and B are foci of ellipse (x-2y+3)^...

If A and B are foci of ellipse `(x-2y+3)^(2)+(8x +4y +4)^(2) =20` andP is any point on it, then `PA +PB =`

A

2

B

4

C

`sqrt(2)`

D

`2sqrt(2)`

Text Solution

Verified by Experts

The correct Answer is:
B
`(x-2y + 3)^(2) + (8x +4y +4)^(2) = 20`
or `(((x-2y+3)/(sqrt(5))))/(4)+(((2x+y+1)/(sqrt(5)))^(2))/((1)/(4)) =1`
`rArr PA + PB = 2a = 4`
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