Question
Show that the lines 
and 
intersect each other.
Solution
The equations of lines are
...(1)
and 
...(2)
Any point on line (1) is (4r + 5, 4r + 7, - 5r -3), It lies on line (2)
if 
i.e, if 
...(3)
From the first and second members,
Substituting this value of r in (3), we get,
or 
∴ the lines intersect at (– 4 + 5, –4 + 7, 5 – 3) i.e. (1,3,2).
