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BITSAT2023MathematicsParabolaActual

If vertex of a parabola is (2,-1) and the equation of its directrix is 4 x-3 y=21 , then the length of its latus rectum is

Options

  1. A2
  2. B8
  3. C12
  4. D16

Correct answer

B. 8

Step-by-step solution

We are given that directrix of the parabola is 4 x-3 y=21 and vertex of the parabola is (2,-1) Now a= |8+3-21| 5 = 10 5 =2 latus rectum of the parabola =4 a=8

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