Parametric equations of a line.

Description
How to find the equation of the line of intersection of two planes is discussed in this video. The trajectory of a moving point is discussed using the parametric equation. The position of such a point at time t is calculated. The parametric equation of a line is derived.
Prof. Denis Auroux, Maths, Fall 2007,18.02 Multivariable Calculus: 5: Parametric Equations, Massachusetts Institute of Technology: MIT OpenCourseWare),http://ocw.mit.edu (Accessed August 15,2011). License: Creative Commons BY-NC-SA:http://ocw.mit.edu/terms/#cc