I just recently (like 2 days ago) got blender 2.5. Can someone tell me where a “Join Triangles” button is?
hotkey Alt J
First, select two adjacent triangular meshes. And in 3D view, menu pick Mesh > Faces > Tris to Quads.
It is nice to know where the functions are when you can’t remember the hot keys.
Or you can just select two triangles and press “F” to fill them into one quad… 