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# triangles angles

Can any one tell me what calculation you have to make to calculate scalene triangles angles if you know all the lengths of the sides?

i am trying to make ik system that will suit my needs and i need to calculate the angles at which my bones should be but i need some angles. i looked on internet but i have no idea how to do all of that in script.

**Answer** by fafase
·
Mar 27, 2013 at 02:50 PM

You have not search real well have you :)

The law of cosines is your answer.

Check there for instance.

http://www.mathsisfun.com/algebra/trig-cosine-law.html

Note that this is more of a math question than a unity question.

```
float AngleOfTriangle(float a, float b, float c){
float cAng = (a*a+b*b- c*c)/(2*a*b);
float rad = Mathf.Acos(cAng);
return Mathf.Rad2Deg(rad);
}
```

In this case, the c angle represents the angle opposite to the last edge provided as parameter.

EDIT: I realized I made one mistake, it was given as a^a+b^b-c^c but it is a*a+b*b-c*c those are squared not power of itself. As requested in Js:

```
function AngleOfTriangle:float(a:float , b:float, c:float){
var cAng:float = (a*a+b*b- c*c)/(2*a*b);
var rad:float = Mathf.Acos(cAng);
return Mathf.Rad2Deg(rad);
}
```

And it is "Can you PLEASE write this in Javascript?" :)

sorry to bother you but i have some errors like: expecting (, found ':'. about 6 of them and does it change anything if im using unity 3.5?

What line? you could remove the :float. The version of Unity does not matter. I am a little rusty on Js...

so try with :

```
function AngleOfTriangle(a:float , b:float, c:float)
```

**Answer** by gsoft9999
·
Mar 27, 2013 at 02:56 PM

thanks a lot!!! i was stuck on this for 5 hours

Check that I modified since I found a mistake in my answer. Also, remove this as you are not answering but commenting my answer :).

**Answer** by gsoft9999
·
Mar 27, 2013 at 03:37 PM

```
function AngleOfTriangle (a:float , b:float, c:float): float{
var cAng:float = (a*a+b*b-c*c)/(2*a*b);
var rad:float = Mathf.Acos(cAng);
return Mathf.Rad2Deg*rad;
}
```

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