ExamBro
ExamBro
MHT CET · Maths · Three Dimensional Geometry

If the line \(\frac{x-1}{-3}=\frac{y-2}{2 k}=\frac{z-3}{2}\) and \(\frac{x-1}{3 k}=\frac{y-5}{1}=\frac{z-6}{-5}\) are perpendicular to each other, then \(k\) is

  1. A \(\frac{7}{10}\)
  2. B \(\frac{10}{7}\)
  3. C \(\frac{-7}{10}\)
  4. D \(\frac{-10}{7}\)
Verified Solution

Answer & Solution

Correct Answer

(D) \(\frac{-10}{7}\)

Step-by-step Solution

Detailed explanation

Given lines are perpendicular. Hence we write
\(
\begin{aligned}
&(-3)(3 \mathrm{k})+(2 \mathrm{k})(1)+(2)(-5)=0 \\
\therefore &-9 \mathrm{k}+2 \mathrm{k}-10=0 \\
\therefore & 7 \mathrm{k}=-10 \Rightarrow \quad \mathrm{k}=\frac{-10}{7}
\end{aligned}
\)