If vertex of a parabola is (2, $-$1) and the equation of its directrix is 4x $-$ 3y = 21, then the length of its latus rectum is :
Solution
<p>Vertex of Parabola : (2, $-$1)</p>
<p>and directrix : 4x $-$ 3y = 21</p>
<p>Distance of vertex from the directrix</p>
<p>$a = \left| {{{8 + 3 - 21} \over {\sqrt {25} }}} \right| = 2$</p>
<p>$\therefore$ length of latus rectum = 4a = 8</p>
About this question
Subject: Mathematics · Chapter: Conic Sections · Topic: Parabola
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