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Question
Find length of latus rectum of the parabola y2 = 4ax passing through the point (2, –6)
Solution
Given the equation of the parabola is y2 = 4ax and it passes through the point (2, –6).
Substituting x = 2 and y = –6 in y2 = 4ax, we get
(–6)2 = 4a(2)
∴ 4a = `36/2` = 18
∴ Length of latus rectum = 4a = 18 units.
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