AP EAMCET202123 Aug 2021Morning ShiftMathematicsCircleActual
If L₁ represents the radical axis of circles x^2+y^2-4 x-6 y+5=0 and x^2+y^2-2 x-4 y-1=0 and L₂ represents the radical axis of x^2+y^2+2 x+2 y-7=0 and x^2+y^2+x+y+9=0 , then
Options
- AL₁ is parallel to L₂ .
- BL₁ is perpendicular to L₂ .
- CL₁ and L₂ intersect at an angle 30^ .
- DL₁ and L₂ intersect at (1,7) .
Correct answer
A. L₁ is parallel to L₂ .
Step-by-step solution
Circles x^2+y^2-4 x-6 y+5=0 (S₁ ) and x^2+y^2-2 x-4 y-1=0 Equation of radical axis is aligned & S₁-S₂=0 & L₁: (x^2+y^2-4 x-6 y+5 )- & (x^2+y^2-2 x-4 y-1 )=0 aligned array ll & -2 x-2 y+6=0 & L₁: x+y-3=0 Similarly, & L₂: (x^2+y^2+2 x+2 y-7 )- & (x^2+y^2+x+y+9 )=0 & L₂: x+y-16=0 array From Eqs. (i) and (ii), we obtain m= coefficient of n coefficient of y m_ L₁ =m_ L₂ =-1 L₁ and L₂ are parallel.