2. Questions Bank
  3. 10th Class
  4. Mathematics
  5. Quadratic Equations

10th Class Mathematics Quadratic Equations Question Bank Quadratic Equation

  • question_answer
    Which of the following are the roots of\[{{\left| y \right|}^{2}}-\left| y \right|-20=0\]?

    A)  \[4\]                            

    B)  \[5\]          

    C)  \[6\]                            

    D)  \[\pm \,5\]

    Correct Answer: D

    Solution :

    (d): \[|y{{|}^{2}}-|y|-20=0\] \[(|y|-5)(|y|+4)=0\] \[|y|=5\]or \[-4\] But\[|y|\]must be non - negative. \[\therefore |y|=5,\]i.e., \[y=\pm 5\]


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