The distance of line

Question:

The distance of line $3 y-2 z-1=0=3 x-z+4$ from the point $(2,-1,6)$ is :

  1. $\sqrt{26}$

  2. $2 \sqrt{5}$

  3. $2 \sqrt{6}$

  4. $4 \sqrt{2}$


Correct Option: , 3

Solution:

$3 y-2 z-1=0=3 x-z+4$

$3 \mathrm{y}-2 \mathrm{z}-1=0 \quad$ D.R's $\Rightarrow(0,3,-2)$

$3 x-z+4=0 \quad$ D.R's $\Rightarrow(3,-1,0)$

Let DR's of given line are $\mathrm{a}, \mathrm{b}, \mathrm{c}$

Now $3 b-2 c=0 \& 3 a-c=0$

$\therefore 6 a=3 b=2 c$

$a: b: c=3: 6: 9$

Any pt on line

$3 \mathrm{~K}-1,6 \mathrm{~K}+1,9 \mathrm{~K}+1$

Now $3(3 \mathrm{~K}-1)+6(6 \mathrm{~K}+1) 1+9(9 \mathrm{~K}+1)=0$

$\Rightarrow \mathrm{K}=\frac{1}{3}$

Point on line $\Rightarrow(0,3,4)$

Given point $(2,-1,6)$

$\Rightarrow$ Distance $=\sqrt{4+16+4}=2 \sqrt{6}$

Option (3)

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