The distance of the point (-1, 2, 6) from the line $\frac{x-2}{6}=\frac{y-3}{3}=\frac{z+4}{-4}$, is equal to :
Answer & explanation
Correct answer: option 1
Any point on the line is
P = (6r1 + 2, 3r1 + 3, –4r1 – 4)
Direction ration of the line segment PQ, where Q = (–1, 2, 6), are
6r1 + 3, 3r1 + 1, – 4r, – 10
If ‘P’ be the foot of altitude drawn from Q to the given line, then
6(6r1 + 3) + 3(3r1 + 1) + 4(4r1 + 10) = 0
⇒ r1 = –1
Thus, P = (–4, 0, 0)
∴ Required distance = $\sqrt{9+4+36}$
= 7 units