Anger is a sign that something isn’t right. Something is wrong. But anger doesn’t fix anything. It usually makes it worse. Replace anger with candidness, no verbosity, drop the adjectives, be specific, focussed and factual. If your mind is rehearsing every angry line that you are going to unleash, you are about to blow it. Be candid, state your case, and listen.
Edit; Oleg (a coworker) just pointed out to me "only ego can be angry, which is not your true self". Couldn't agree more.