AP EAMCET20224 Jul 2022Evening ShiftMathematicsCircleActual
The ratio of the largest and shortest distances from the point 2 , - 7 to the circle x 2 + y 2 - 14 x - 10 y - 151 = 0 is
Options
- A15 : 13
- B7 : 1
- C3 : 2
- D14 : 1
Correct answer
D. 14 : 1
Step-by-step solution
Given equation of circle, x 2 - 14 x + 49 + y 2 - 10 y + 25 - 74 - 151 = 0 On rearranging we get, x - 7 2 + y - 5 2 = 225 ⇒ x - 7 2 + y - 5 2 = 15 2 So, Centre = 7 , 5 and Radius = 15 units Now putting x = 2 & y = - 7 In the clrcle's equation, - 5 2 + - 12 2 - 225 < 0 So, 2 , - 7 lies inside the circle. Now distance from 2 , - 7 to 7 , 5 = x 2 - x 1 2 + y 2 - y 1 2 D = 7 - 2 2 + 5 - - 7 2 D = 5 2 + 12 2 = 13 Now shortest distance will be r - 13 = 15 - 13 = 2 And largest distance will be r + 13 = 15 +