# Angles and graphs, basic question

1. Mar 19, 2009

### darkelf

Hi,

Is there a way of calulating the angles from the slope or coordinates of a graph. Say you have a bunch of x and y coordinates and you want to find the angles between those points at various coordinates (say every x,y ratio) can it be done?
How would you go about it?

2. Mar 20, 2009

### skand

yes,why not. :)

Angle between lines joining $$(x_1,y_1) \&\(x_2,y_2)=tan^{-1}\left( \frac{y_2-y_1}{x_2-x_1}\right)$$

Last edited: Mar 20, 2009
3. Mar 20, 2009

### darkelf

Angles between lines joining? If you have a single slope that doesnt intercept at the x or y axis?

4. Mar 24, 2009

### Cantab Morgan

Have another look at skand's answer. Slope means rise over run, right? So if you have the slope, then you have the tangent of the angle.