Use the links for more practice.
https://www.youtube.com/watch?v=ZSykEIJQSVs
https://www.youtube.com/watch?v=ASFHlTgdNkE
http://www.khanacademy.org/math/algebra/linear-equations-and-inequalitie/more-analytic-geometry/v/distance-formula
http://www.brightstorm.com/math/trigonometry/pythagorean-theorem/distance-formula/
HW: Complete the 6 problems on WS 4.4 (for 4 - 9, pick one row to do depending on which method you prefer).