2. Sample Papers
  3. Railways

Railways Sample Paper RRB (Group D) Sample Test Paper-8

  • question_answer
    The value of k for which the lines \[2x+ky+7=0\]and\[18y+25=0\]are perpendicular to each other, is

    A)  K=\[-\,1\]         

    B)  k=2

    C)  K=3    

    D)  k=\[-\,2\]

    Correct Answer: C

    Solution :

    [c] \[2x+ky+7=0\Rightarrow ky=-\,2x-\,7\Rightarrow \] \[y=\frac{-\,2}{k}x-\,\frac{7}{k}\] \[27x+18y+25=0\Rightarrow 18y=27x+25\] \[\Rightarrow y=\frac{3}{2}x+\frac{25}{18}\] \[\therefore \frac{-2}{k}\times \frac{3}{2}=1\Rightarrow k=3\]


You need to login to perform this action.
You will be redirected in 3 sec spinner