KCET2013MathematicsCircle
A tangent is drawn to the circle 2 x²+2 y²-3 x+4 y=0 at point A and it meets the line x+y=3 at B(2,1) , then A B is equal to
Options
- A10
- B2
- C2 2
- D0
Correct answer
B. 2
Step-by-step solution
Equation of circle is, array r S 2 x²+2 y²-3 x+4 y=0 S x²+y²- 3 2 x+2 y=0 array Here, A B is the length of tangent to the circle from B i.e., aligned A B &= (2)²+(1)²- 3 2 (2)+2(1) &= 4+1-3+2 = 4 &=2 units aligned