AP EAMCET202018 Sep 2020Evening ShiftMathematicsCircleActual
Consider the family of circles (x^2+y^2-2 x-2 y-8=0 ) which passes through two fixed points (A ) and (B ) distance between them is
Options
- A4
- B(4 2 )
- C6
- D8
Correct answer
C. 6
Step-by-step solution
( aligned x^2+y^2-2 x-2 y-8 & =0 (x^2+y^2-2 x-8 )- (2 y) & =0 x^2+y^2-2 x-8 & =0 and 2 y=0 y=0 x^2-2 x-8 & =0 aligned ) Distance between points (A, B= |x₁-x₂ | ) ( aligned & = D |a| = b^2-4 a c |a| & = 4-4 1(-8) 1 = 36 =6 aligned ) Hence, option (c) is correct.