UPSC NDA I 2015 Mathematics Solved Paper

The inclination of the line with the positive x-axis gives the slope of the line.
Therefore the equation of the line will be of the form
y=tan(120°)x+d
y=−tan(60°)x+d
y=−√3x+d
Now it is given that the distance between the line and the origin is 5 units.
Hence,
dorigin=

|y0+√3x0−d|

√1+(√3)2

=5

|d|

2

=5
|d|=10
d=±10
y+√3x=±10