AP EAMCET202023 Sep 2020Morning ShiftMathematicsCircleActual
The radius of the circle 2 x 2 + 2 y 2 - 3 x + 2 y - 1 = 0 is _________ units.
Options
- A21 2 units
- B21 4 units
- C21 4 units
- D5 4 units
Correct answer
B. 21 4 units
Step-by-step solution
2 x 2 + 2 y 2 - 3 x + 2 y - 1 = 0 ⇒ x 2 + y 2 - 3 2 x + y - 1 2 = 0 r = g 2 + f 2 - c g = - 3 4 ,   f = 1 2 ,   c = - 1 2 r = 9 16 + 1 4 + 1 2 ⇒ r = 9 + 4 + 8 16 r = 21 4 units.