AP EAMCET201824 Apr 2018Morning ShiftMathematicsCircleActual
If the shortest distance from (2,-14) to the circle x^2+y^2+6 x+4 y-12=0 is d and the length of the tangent drawn from the same point to the circle is l , then d+l =
Options
- A13
- B2 5
- C12
- D5
Correct answer
B. 2 5
Step-by-step solution
Given circle, x^2+y^2+6 x+4 y-12=0 Here, centre is O(-3,-2) and radius = 9+4+12 = 25 =5 Shortest distance of the point P(2,-14) to the circle is circle is aligned A P & =d A P & =O P-O A (O A & =R) O P & = (-3-2)^2+(-2+14)^2 & = 25+144 = 169 =13 A P & =13-5=8=d aligned Length of tangent from the point P(2,-14) is aligned & = (2)^2+(-14)^2+6 2+4(-14)-12 & = 4+196+12-56-12 & = 144 =12=1 aligned So, required d+l = 8+12 = 20 =2 5 .