2. Questions Bank
  3. 10th Class
  4. Mathematics
  5. Related to Competitive Exam

10th Class Mathematics Related to Competitive Exam Question Bank Algebra

  • question_answer
    If \[2{{x}^{2}}+xy-3{{y}^{2}}+x+ay-10=\]\[(2x+3y+b)\]\[(x-y-2)\],the value of a and b are

    A)  11 and 5

    B)  1 and - 5              

    C)  - 1 and - 5                           

    D)  - 11 and 5                             

    Correct Answer: D

    Solution :

     \[2{{x}^{2}}+xy-3{{y}^{2}}+x+ay-10\]                 \[=(2x+3y+b)(x-y-2)\] \[=2{{x}^{2}}+xy-3{{y}^{2}}+(b-4)x-(b+6)y-2b\] Compare the coefficients of \[x,\,\,y\] and constant on both sides, we get                 \[b-4=1\],            \[\Rightarrow \]               \[b=5\]                 \[-(b+6)=a\],      \[\Rightarrow \]               \[a=-11\] and        \[2b=10\]            \[\Rightarrow \]               \[b=5\]


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