JEE Main & Advanced Mathematics Straight Line Question Bank Critical Thinking

  • question_answer
    The number of integral values of m, for which the x-co-ordinate of the point of intersection of the lines \[3x+4y=9\] and \[y=mx+1\]is also an integer is  [IIT Screening 2001]

    A)            2

    B)            0

    C)            4     

    D)            1

    Correct Answer: A

    Solution :

               Solving \[3x+4y=9,\,y=mx+1\] we get \[x=\frac{5}{3+4m}\]                    x is an integer if \[3+4m=1,\,-1,\,5,\,-5\]                    \ \[m=\frac{-2}{4},\,\frac{-4}{4},\,\frac{2}{4},\,\frac{-8}{4}\]. So, m has two integral values.

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