2. Solved Papers
  3. CET Karnataka Engineering

CET Karnataka Engineering CET - Karnataka Engineering Solved Paper-2006

  • question_answer
    If the lines \[x+3y-9=0,4x+by-2=0\] and \[2x-y-4=0\] are concurrent, then b equals :

    A)  -5                                          

    B)  5

    C)  1                                            

    D)  0

    Correct Answer: A

    Solution :

    Since the lines \[x+3y-9=0,\] \[4x+by-2=0\] and \[2x-y-4=0\]are concurrent, then                                 \[\left| \begin{matrix}    1 & 3 & -9  \\    4 & b & -2  \\    2 & -1 & -4  \\ \end{matrix} \right|=0\] \[\Rightarrow \]\[1(-4b-2)-3(-16+4)-9(-4-2b)=0\] \[\Rightarrow \]               \[-4b-2+36+36+18b=0\] \[\Rightarrow \]               \[14b+70=0\] \[\Rightarrow \]               \[b=-5\]


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