Eliminating anger involves seeing the true nature of reality.
When you realize the nature of reality you can no longer divide it into real bits. Within this undivided realm the interdependence of all phenomena is clear and you can no longer identify individual causes or results. Here there is no anger because it is impossible to identify a clear source or cause of the situation.
There is a Buddhist story illustrating this…
A man in a crowd was hit by a stick. He cursed the stick. Someone said to him, “Do not curse the stick. It is only a piece of wood and cannot act alone. If you want, curse the hand that holds the stick. The man agreed and shouted at the hand. The onlooker said, “No… not the hand itself, rather the person whose hand it is. The man agreed and vented his anger on the man holding the stick. “No, no, no said the onlooker… curse all the factors that caused this behavior of the man”. But then he was lost. This was completely impossible.
Eliminating anger involves no more than seeing the true face of reality. Then life is easier.