Question
Find the vector and Cartesian equations of the line through the point (5, 2, – 4) and which is parallel to the vector
Solution
Since the line passes through the point (5, 2, 4) and is parallel to the vector 

Let
be the position vector of any point on the line.
∴ the vector equation of line is

or
Taking
the equation of line is

Comparing the coefficients of
we get,

or
which is cartesian equation of line.


Let

∴ the vector equation of line is

or

Taking


Comparing the coefficients of


or

which is cartesian equation of line.