JEE Mains · Maths · STD 11 - 10.2 parabola,ellipse,hyperbola
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
- A \(2\)
- B \(8\)
- C \(12\)
- D \(16\)
Answer & Solution
Correct Answer
(B) \(8\)
Step-by-step Solution
Detailed explanation
\(a=\frac{|8+3-21|}{5}=\frac{10}{5}=2\) \(\therefore\) latus rectum \(=4 a=8\)
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