JEE Main & Advanced Mathematics Circle and System of Circles Question Bank Equations of circle, Geometrical problems regarding circle

  • question_answer
    If the lines \[2x+3y+1=0\]and \[3x-y-4=0\]lie along diameters of a circle of circumference \[10\pi \], then the equation of the circle is                                                                            [AIEEE 2004]

    A)            \[{{x}^{2}}+{{y}^{2}}+2x-2y-23=0\]                            

    B)            \[{{x}^{2}}+{{y}^{2}}-2x-2y-23=0\]

    C)            \[{{x}^{2}}+{{y}^{2}}+2x-2y-23=0\]

    D)            \[{{x}^{2}}+{{y}^{2}}-2x+2y-23=0\]

    Correct Answer: D

    Solution :

               According to question two diameters of the circle are \[2x+3y+1=0\] and \[3x-y-4=0\] Solving, we get \[x=1,\,y=-1\] \[\therefore \] Centre of the circle is (1, ? 1) Given \[2\pi r=10\pi \Rightarrow r=5\] \[\therefore \] Required circle is \[{{(x-1)}^{2}}+{{(y+1)}^{2}}={{5}^{2}}\] or \[{{x}^{2}}+{{y}^{2}}-2x+2y-23=0\].


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