2. Solved Papers
  3. JEE Main & Advanced

JEE Main & Advanced JEE Main Paper (Held On 12 April 2014)

  • question_answer
    If the three distinct lines x + 2ay + a = 0, x + 3by + b = 0 and x + 4ay + a = 0 are concurrent, then the point (a, b) lies on a:   [JEE Main Online Paper ( Held On 12 Apirl  2014 )

    A) circle                     

    B) hyperbola

    C) straight line       

    D) parabola

    Correct Answer: C

    Solution :

    \[x+2ay+a=0\]                                                   ...(1) \[x+3by+b=0\]                                                  ...(2) \[x+4ay+a=0\]                                                   ...(3) Subtracting equation (3) from (1) \[-2ay=0\] \[ay=0\Rightarrow y=0\] Putting value of y in equation (1), we get \[x+0+a=0\] \[x=-a\] Putting value of x and y in equation (2), we get a + b = 0 a = b Thus, (a, b) lies on a straight line


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