The distance of origin from line 1+3y+1−3x=10 measured along the line y=3x+4 is
52
52+k
10
5
Slope of the line L≡1+3y+1−3x=10 is
3−13+1=tan150
Slope of line y=3x+k is 3=tan600
In the figure, distance of origin from line L measured along the line y=3x+k is OP
From the figure,
OP=OM sec450
=0+0−103−12+3+122=1082=5