Question
Question: The length of the latusrectum of the parabola (5x - 12y + 17)<sup>2</sup> = 169\(\left\lbrack (x - 1...
The length of the latusrectum of the parabola (5x - 12y + 17)2 = 169[(x−1)2+(y−3)2] is
A
14/13
B
28/13
C
12/13
D
24/13
Answer
28/13
Explanation
Solution
Given parabola is (x-1)2 + (y-3)2 = (135x−12y+17)2
This s the form SP2 = PM2
Where S = (1, 3) = focus
5x – 12y + 17 = 0 is the directrix.
∴ Length of latusrectum = 2 x (perpendicular distance from focus to directrix)
= 2 x 1314 = 28/13.