Three Dimensional Geometry Question 321

Question: The distance of the point of intersection of the line $ \frac{x-3}{1}=\frac{y-4}{2}=\frac{z-5}{2} $ and the plane $ x+y+z=17 $ from the point (3, 4, 5) is given by

Options:

A) 3

B) 3/2

C) $ \sqrt{3} $

D) None of these

Show Answer

Answer:

Correct Answer: A

Solution:

Any point on the line $ \frac{x-3}{1}=\frac{y-4}{2}=\frac{z-5}{2} $ is $ (r+3,2r+4,2r+5) $ which satisfies the plane. So, $ r+3+2r+4+2r+5=\Rightarrow r=1. $

$ \therefore $ The point is (4, 6, 7).
Hence required distance is $ \sqrt{1^{2}+2^{2}+2^{2}}=3. $