JEE Main2016MathematicsStraight LinesActual
A straight line through origin O meets the lines 3 y = 10 - 4 x and 8 x + 6 y + 5 = 0 at points A and B respectively. Then, O divides the segment A B in the ratio
Options
- A2 : 3
- B1 : 2
- C4 : 1
- D3 : 4
Correct answer
C. 4 : 1
Step-by-step solution
Let A r 1 cos θ ,   r 1 sin θ A Lies on straight line 4 x + 3 y = 10 ⇒ 4 r 1 cos θ + 3 r 1 sin θ = 10 ⇒ r 1 4 cos θ + 3 sin θ = 10 ⇒ r 1 = 10 4 cos θ + 3 sin θ Let B - r 2 cos θ ,   - r 2 sin θ B lies on line 8 x + 6 y + 5 = 0 ⇒ 8 - r 2 cos θ + 6 - r 2 sin θ + 5 = 0 ⇒ r 2 8 cos θ + 6 sin θ - 5 = 0 ⇒ r 2 = 5 8 cos θ + 6 sin θ ∴ r 1 r 2 = 4 1