# Limits and Rates of Change

1. Sep 12, 2010

### thats.life

Hello there. I am kind of confused about this and have no idea where to start.
FOr example:

If the line given is y=x^2+4x-1 and we are to find the slope of the tangent of the perpendicular line which passes through x-coordinate -3.

Where do I start?

2. Sep 12, 2010

### LCKurtz

Figure out what point (-3, ?) you are discussing. Then, do you know how to find the slope of a curve at a point? And do you know the relation between the slopes of two lines which are perpendicular to each other?

3. Sep 12, 2010

### thats.life

Ohh I am sorry. Disregard the perpendicular part.
So what I am asking is:

How do i find the sloper of the tangent lines to the parabola y= x^2 + 4x -1 if I am only given the x-coordinate -3. That is all the information stated.

I need help from step one. I have no idea how to even approach this.

4. Sep 12, 2010

### LCKurtz

Well, surely you can figure out the y value for x = -3.

Are you taking a calculus course? Do you know about derivatives and their relation to slope?

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