NTA Abhyas JEE Main2020MathematicsCirclePractice
Let the lines 4 x - 3 y + 10 = 0 and 4 x - 3 y - 30 = 0 make equal intercepts of 6 units with a circle C whose centre lies on 2 x + y = 0 , then the equation of the circle C is
Options
- Ax 2 + y 2 - 2 x + 4 y - 20 = 0
- Bx 2 + y 2 - 4 x + 8 y - 20 = 0
- Cx 2 + y 2 + 2 x - 4 y - 20 = 0
- Dx 2 + y 2 - 4 x + 8 y - 5 = 0
Correct answer
A. x 2 + y 2 - 2 x + 4 y - 20 = 0
Step-by-step solution
Centre of the circle C lies on 2 x + y = 0 & 4 x - 3 y + 10 - 30 2 = 0 ⇒ Center of C is 1 , - 2 Radius of C is 3 2 + 4 2 = 5 Equation of C is x - 1 2 + y + 2 2 = 5 2 ⇒ x 2 + y 2 - 2 x + 4 y - 20 = 0