Rotation of a point about another point

Hi,

I have run into an issue a few times in my project where I have to rotate an object or a point around a specific center. I am currently solving the issue like this:

Code (CSharp):

1.          
2. GameObject ro = new GameObject();
3. ro.transform.position = rotationobject.transform.position;
4. ro.transform.rotation = Quaternion.identity;
5.  
6. GameObject go = new GameObject();
7. go.transform.position = pos;
8.  
9. go.transform.parent = ro.transform;
10.  
11. ro.transform.rotation = rotationobject.transform.rotation;
12.  
13. go.transform.parent = null;
14.              
15.  

Which is obviously messy, but it does work.

What is the correct way to solve this? I'm guessing there is purely mathematical way, involving quaternions/matrices, possibly, and not creating gameobjects?

Or could I use transform.rotatearound?