The distance of the point (1,1,9) from the point

Question:

The distance of the point $(1,1,9)$ from the point

of intersection of the line $\frac{x-3}{1}=\frac{y-4}{2}=\frac{z-5}{2}$

and the plane $x+y+z=17$ is:

 

  1. $2 \sqrt{19}$

  2. $19 \sqrt{2}$

  3. 38

  4. $\sqrt{38}$


Correct Option: , 4

Solution:

Let $\frac{x-3}{1}=\frac{y-4}{2}=\frac{z-5}{2}=t$

$\Rightarrow \quad x=3+t, y=2 t+4, z=2 t+5$

for point of intersection with $x+y+z=17$

$3+t+2 t+4+2 t+5=17$

$\Rightarrow 5 \mathrm{t}=5 \Rightarrow \mathrm{t}=1$

$\Rightarrow$ point of intersection is $(4,6,7)$

distance between $(1,1,9)$ and $(4,6,7)$

is $\sqrt{9+25+4}=\sqrt{38}$

 

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