How to derive the formula to find out the distance between a given point and given line. More free lessons at: http://www.khanacademy.org/video?v=eF6zYNzlZKQ Note: All Khan Academy content is available for free at (www.khanacademy.org)

How to derive equations for parallel and perpendicular lines. More free lessons at: http://www.khanacademy.org/video?v=eF6zYNzlZKQ Note: All Khan Academy content is available for free at (www.khanacademy.org)

Derivation of Distance Formula. More free lessons at: http://www.khanacademy.org/video?v=eF6zYNzlZKQ Note: All Khan Academy content is available for free at (www.khanacademy.org)