This was pretty neat. I liked the simplicity of the gameplay and the way it scaled up in difficulty, but I found that it was sometimes really difficult to place the vertices without accidentally creating an invalid triangle and losing my goats. I also think that sometimes the camera angle made it a little difficult to see whether or not a goat was going to land on the triangle or the ground. I can see that there's a lot of room to build on this idea, though, and I think what's there right now makes for a deceptively difficult little casual game. Nice work!