AP EAMCET201825 Apr 2018Morning ShiftMathematicsStraight LinesActual
The circumcentre of the triangle with vertices at ( - 2 , 3 ) , ( 1 , - 2 ) and ( 2 , 1 ) is
Options
- A6 7 , 2 7
- B- 6 7 , 2 7
- C6 7 , - 2 7
- D- 6 7 , - 2 7
Correct answer
B. - 6 7 , 2 7
Step-by-step solution
Circumcentre of the triangle is equidistant from the vertices of the triangle. Let O x , y be the circumcentre of the triangle. Now, O A = x + 2 2 + y - 3 2     . . . i O B = x - 1 2 + y + 2 2     . . . ii O C = x - 2 2 + y - 1 2     . . . iii O A = O B = O C Equating i   &   ii , we get x + 2 2 + y - 3 2 = x - 1 2 + y + 2 2 ⇒ x + 2 2 + y - 3 2 = x - 1 2 + y + 2 2 3 x - 5 y + 4 = 0     . . . iv Equating ii   &   iii , we get x - 1 2 + y + 2 2