Question

The equation of a line, having inclination 120° with positive direction of X-axis, which is at a distance of 3 units from the origin is

(a) √3x ± y + 6 = 0

(b) √3x + y ± 6 = 0

(c) x + y = 6

(d) x + y = -6

Answer 1

Correct option is : (b) √3x + y ± 6 = 0

Here, α = 30° and p = 3 units 

Equation of line with inclination a and distance from origin as p is x cos α + y sin α = p

∴ x cos 30° + y sin 30° = ±3

∴ √3x/2 + y/2 = ± 3

∴ √3x + y ± 6 = 0