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Question
Select the correct option from the given alternatives:
If the line 4x − 3y + k = 0 touches the ellipse 5x2 + 9y2 = 45 then the value of k is
Options
+ 21
`± 3sqrt(21)`
+ 3
+ 3(21)
Solution
If the line 4x − 3y + k = 0 touches the ellipse 5x2 + 9y2 = 45 then the value of k is `± 3sqrt(21)`
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