How do Tom, Jordan, and Nick find out about the accident in The Great Gatsby?
Tom, Nick, and Jordan arrive near Wilson's shop after the accident has occurred. Tom slows down just to get a look, but then decides to go into the garage to see what has happened. Pushing his way through the crowd of people, Tom makes his way into the garage. By this time, Nick and Jordan also find their way in through the circle of bystanders:
The circle closed up again with a running murmur of expostulation; it was a minute before I could see anything at all. Then new arrivals deranged the line, and Jordan and I were pushed suddenly inside. (Chapter 7)
Tom learns from a policeman that Myrtle was instantly killed by a car. Michaelis, the young Greek man who owned a coffee shop nearby, witnessed the accident. Another man noted that it was a big, yellow car that hit Myrtle. Wilson concludes that he knows what kind of car it was. Since Tom had driven Gatsby's yellow car into town that day, and stopped at Wilson's garage for gas, Tom lets Wilson know that he hadn't seen the car since then. Speaking to George Wilson, Tom says,
I just got here a minute ago, from New York. I was bringing you that coupe we’ve been talking about. That yellow car I was driving this afternoon wasn’t mine—do you hear? I haven’t seen it all afternoon.
Tom, Nick, and Jordan return to Tom's place. Daisy is already there. Tom and Jordan go inside while Nick waits for a taxi. Nick discovers Gatsby waiting outside; he tells Nick he wants to protect Daisy from Tom. Gatsby informs Nick that Daisy had been driving but he (Gatsby) intends to say that he was driving the car.