Late letters of recommendation

<p>Hey guys, Im a high school senior applying to Harvey Mudd, Caltech, and Stanford, and the deadlines are coming up. Yet my teacher that I asked for a letter of recommendation still has not completed it. Im pretty panicked and I emailed one of my other teachers, asking if he would write me one if the other teacher did not respond, and he agreed. So I was just wondering if it would be better to submit the letters about 2 weeks late to the schools, because they will allow it, or just have the other teacher write the letter now? Because I would rather have the first teacher write it but I dont want it to lower my chances of getting in.</p>