1. The problem statement, all variables and given/known data Find an equation of the normal line to the parabola y = x^2 - 5x + 4 that is parallel to the line x - 3y = 5. 2. Relevant equations ? All that is relevant is mentioned below AFAIK. 3. The attempt at a solution Here is my attempt: http://screencast.com/t/oXxI6JPHv My book says the solution is supposed to be y = 1/3x - 1/3 I also found this: http://answers.yahoo.com/question/i...L8aRlYEjzKIX;_ylv=3?qid=20071125140023AAebnO1 It's the exact same problem and algebraically, I arrive at the same results as the person who answered the question there. I also don't see that the negative reciprocal of the slope was taken anywhere. After all, I need to find the equation of the normal line to the parabola and not the equation of the tangent line. What am I missing?