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## Homework Statement

Find an equation of the normal line to the parabola y = x^2 - 5x + 4 that is parallel to the line x - 3y = 5.

## Homework Equations

? All that is relevant is mentioned below AFAIK.

## 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?

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