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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 - Mathematics and Statistics

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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)

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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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Chapter 7: Conic Sections - Miscellaneous Exercise 7 [Page 177]

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Balbharati Mathematics and Statistics 1 (Arts and Science) [English] Standard 11 Maharashtra State Board
Chapter 7 Conic Sections
Miscellaneous Exercise 7 | Q I. (14) | Page 177

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