https://apnews.com/16a31c10037cdc19aea4e92d528c649f > Elon Musk is joining Twitter's board of directors a day after disclosing that the Tesla CEO took a 9% stake in the social media platform. > Twitter Inc. said in a regulatory filing Tuesday that it entered into an agreement with Musk on Monday that will give the billionaire a seat on its board, with the term expiring at its 2024 annual shareholders meeting.