Q61 / 180 · KCET 2021 · Mathematics
The equation of the line joining the points $(-3,4,11)$ and $(1,-2,7)$ is
- A$\frac{x+3}{2}=\frac{y-4}{3}=\frac{z-11}{4}$
- Correct answerB$\frac{x+3}{-2}=\frac{y-4}{3}=\frac{z-11}{2}$
- C$\frac{x+3}{-2}=\frac{y+4}{3}=\frac{z+11}{4}$
- D$\frac{x+3}{2}=\frac{y+4}{-3}=\frac{z+11}{2}$
Solution
Given, points are $(-3,4,11)$ and $(1,-2,7)$.
Let $A(-3,4,11)$ and $B(1,-2,7)$
Direction ratios of $A B=1-(-3),-2-4,7-11$
$=4,-6,-4$
$=-2,3,2$
Now, we have one point $(-3,4,11)=\left(x_{1}, y_{1}, z_{1}\right)$ and direction ratios $(a, b, c)=-2,3,2$
$\because$ Equation of line :
$\begin{aligned}
& \frac{x-x_{1}}{a}=\frac{y-y_{1}}{b}=\frac{z-z_{1}}{c} \\
\Rightarrow \quad \frac{x+3}{-2} &=\frac{y-4}{3}=\frac{z-11}{2}
\end{aligned}$
Hence, the correct answer is option: 'B'.